Exercise in patients with tension-type headache
a systematic review and meta-analysis
Elin Rundström
Physiotherapy, master's level (120 credits) 2021
Luleå University of Technology Department of Health, Learning and Technology
Abstract:
Objective: This meta-analysis reviews the evidence for training in patients with tension-type headache on pain intensity and headache frequency.
Method: Electronic databases were searched for randomized controlled trials evaluating training on patients with tension-type headache. Data was extracted by the reviewer.
Methodological quality was assessed using risk of bias two and a meta-analysis was made using Revman 5. The quality of the evidence was calculated using GRADEproGDT.
Results: Regarding pain intensity four studies were included (n = 330 participants). The meta-analysis indicates that training is effective in reducing pain intensity in patients with tension-type headache. This result does not reach a clinical important difference. The quality of evidence is moderate. For headache frequency three studies were included in the
meta-analysis (n = 290 participants). The meta-analysis showed that training is effective in reducing headache frequency in patients with tension-type headache. This change does not reach a clinical important difference. The quality of evidence for this result is high.
Conclusion: There is moderate quality of evidence that exercise reduces pain intensity in patients with tension-type headache. There is high quality evidence that exercise reduces headache frequency in patients with tension-type headache. Neither of these results reach a clinically important difference. This may be due to the active control groups and needs to be researched further.
Keywords:
Exercise, Headache frequency, Meta-analysis, Pain intensity, Tension-type headache, Training
1. Introduction:
The lifetime prevalence for tension-type headache ranges between 30-78% (1). The
prevalence is higher in women (86%) than in men (63%) and is decreased with increasing age (1). It has a high socio-economic impact (2) and its impact on the patients quality of life and disability is high (1, 2, 3). The international headache society classifies four types of primary headaches: migraine, tension-type headache, trigeminal autonomic cephalgias and other primary headaches. Within the tension-type group there are four different types of headaches:
infrequent episodic tension-type headache, frequent episodic tension-type headache, chronic tension-type headache and probable tension-type headache. These have the same
characteristics: it is typically bilateral and is described as a tightening or pressing quality. It is often of mild to moderate intensity and it does not get worse with exercise. Tension-type headache is not associated with nausea, but photophobia and/or phonophobia may occur (2).
The pathology of tension-type headache is unknown. Several theories exist, where some describe tension-type headache as a peripheral pain mechanism while others describe a central pain mechanism. One of the many theories that exists is that muscles and the
activation of musculoskeletal nociceptors is the cause of frequent and episodic tension-type headache. When these episodes happen repeatedly a sensitization of the central nervous system can lead to the development of chronic tension-type headache (4). Studies have shown that people with tension-type headache have a pressure pain hypersensitivity in the trigeminal and cervical area compared to healthy controls (5, 6). This pericranial tenderness is described as a peripheral nociception (2, 7, 8). In patients with chronic tension-type headache the hypersensitivity was widespread (6). Patients with chronic tension-type headache also have decreased mechanical, thermal and pain thresholds which probably represents a central pain mechanism (2, 7, 8). According to the international headache society the most likely cause of episodic tension-type headache is peripheral pain mechanisms whereas chronic tension-type headache is more likely to be a cause of central pain mechanisms (2).
Many patients with tension-type headaches also have neck pain to some degree. Some studies report findings of cervical musculoskeletal dysfunction in patients with tension-type
headache compared to controls (9, 10) while others do not (11). Decreased muscle strength of
isometric strength of the neck flexors a decrease in pain pressure scores have been seen. This is seen as an expression of a reduction in both peripheral and central pain mechanisms (5).
Strength training and aerobic exercise has a positive effect regarding sleep (13), mood (14, 15, 16, 17), and physical performance (15, 16, 17). These factors in themselves can have a positive effect on patients' pain perception. It also has a hypo analgesic effect (15, 16, 18, 19, 20, 21) and an effect on both peripheral and central pain modulation (22). Exercise-induced hypoalgesia is a reduction of pain both during and after exercise. This is proven for both aerobic and anaerobic exercise (18, 19, 23). Exercise-induced hypoalgesia is present within 30 min or more after one training session. This has been proven to occur in healthy
individuals. When it comes to people with chronic pain the relation is not as clear and more studies are needed (24, 25). Exercise therefore can be a relevant intervention for patients with peripheral pain mechanisms, as is the probable cause of episodic tension type headache, and for patients with pain of central pain mechanisms which is the likely cause of chronic headache.
Whilst there are several studies that research the effect of training on pain intensity and headache frequency in patients with tension-type headache (26, 27, 28, 29, 30, 31), there is to the authors knowledge no systematic review or meta-analysis on the subject. This review is therefore an attempt to clarify the effect and evidence of training on tension type headache.
2. Purpose:
This meta-analysis reviews the evidence for training in patients with tension-type headache on pain intensity and headache frequency.
3. Method:
3.1 Design:
A systematic review of randomized controlled trials (RCT) and a meta-analysis was made in order to establish the evidence within the field. In order to make a systematic review the author needs to assess the quality of the articles and evaluate their risk of bias and
methodological quality (32, 33). In this review the PRISMA checklist was followed (34) (See the whole checklist in Appendix E) (https://prisma.shinyapps.io/checklist/) a risk of bias analysis: risk of bias 2 (RoB2) was made, the meta-analysis was conducted using the program Revman 5
(https://training.cochrane.org/online-learning/core-software-cochrane-reviews/revman/revma n-5-download) and theGrading of Recommendations, Assessment, Development and
Evaluation:GRADEproGDT(https://gradepro.org/)was used to grade the quality of the results.
3.2 PICO:
- Population: adults age 18-65, diagnosed with tension-type headache according to the international classification of headache disorders (2).
- Intervention: training.
- Control: control group or other intervention.
- Outcome: pain intensity and headache frequency.
3.3 Search strategy and study selection:
An electronic search was carried out in PubMed, Cinahl and Web of science. The
combination of these three databases was used to cover and discover all RCT’s relevant to the review's purpose. In order to include all the relevant articles various words for exercise and tension-type headache were used. The search strategy as a whole is enclosed in Appendix A.
The author first identified studies relevant for the review by their title and then read the abstract. The articles that were still considered relevant were read through to identify the studies relevant for inclusion (Figure 1). During the whole process of identifying relevant studies the reviews’ PICO was used to include and exclude studies.
- Inclusion criteria: Relevant population, intervention, control and outcome (PICO).
RCTs conducted after 2004 (the international classification of headache disorders, 2nd edition that was released in 2004). The articles had to be published in a scientific journal in English or Swedish in order to be included. The articles also had to be peer reviewed.
- Exclusion criteria: other pathologies or medical conditions such as post-traumatic headache, migraine and rheumatic disorders. Articles that included patients with mixed headaches. Studies that were judged as having a high risk of bias were excluded from the review and meta-analysis.
3.5 Risk of bias:
In order to assess the included studies’ methodological quality an evaluation of the included studies’ risk of bias was made using the revised risk-of-bias tool for randomized trials; RoB 2 (32, 35) (https://sites.google.com/site/riskofbiastool) . The studies were judged as “low risk”,
“of some concerns” or “high risk” using the RoB2 algorithms. This was made for each of the domains and for the overall methodological quality of the studies (35).
3.6 Data extraction:
The author initially extracted data from all relevant studies by making an excel table containing the number of participants, type of headache, intervention, control and primary and secondary outcomes that were relevant for the review's purpose. The studies were read through and the relevant data was extracted (mean, SD, p-value). In one case where this data was not available, the author of the article was contacted in order to obtain the relevant data (29). Although several attempts were made, no answer was given. The author then contacted the supervisor in order to convert the data that was provided in the article.
3.7 Data analysis:
The meta-analyses were made using the software Revman 5
(https://training.cochrane.org/online-learning/core-software-cochrane-reviews/revman/revma n-5-download) . In this case the analyses were made using the articles mean and standard deviation to calculate the standardized mean difference. The standardized mean difference is
one case, the information in the article was confidence interval rather than standard deviation (26). Therefore a calculation to convert the data into standard deviation was conducted. In the study where there was missing data (29) the supervisor of this review helped the author by using the RevMan Calculator (https://training.cochrane.org/resource/revman-calculator) in order to convert the data into mean and SD-values that could be used in the meta-analysis. In order to clarify the achieved improvement of the interventions the percentage of the
improvement was calculated by calculating the pre- and post intervention mean-values for each group (Table 1). In order to assess the clinically important difference of the interventions the pooled effects of the mean differences and the 95% confidence intervals were used. This was calculated in the meta-analysis and then converted into percentage. For interpretation of the treatment effects a small effect size was set at 10%, a medium effect size was set at 10-20% and a high effect was set as more than 20% (36).In order to make this calculation it is important that all of the studies use the same scale, this was the case for the outcome pain intensity where all studies used a 0-10 scale. For the outcome headache frequency however, two of the studies used days/month (26, 28) and one study used days/week (29). The latter was therefore calculated into days/month in order to make this comparison.
3.8 Quality of evidence:
To assess the overall quality of evidence of the included studies a ‘summary of findings table’
was made for each outcome measure using GRADEpro GDT (https://gradepro.org/). By evaluating and grading the study design, risk of bias, inconsistency, indirectness and
imprecision of the included studies and adding the data from the meta-analyses in Revman 5 the program creates a summary of findings table and calculates an overall evaluation of the included studies’ quality of evidence. In order to define the level of evidence the program takes into consideration factors that can reduce the quality of evidence (study design, inconsistency of the results, indirectness of evidence, impression and publication bias) and factors that can increase the quality of evidence (large magnitude of effect, dose response gradient and all plausible confounding)(see the full handbook on
https://gdt.gradepro.org/app/handbook/handbook.html#h.dce0ghnajwsm). This is conducted in order to rate the certainty of the evidence in the included studies. When conducting a GRADE evaluation the definitions of the quality of evidence is as follows:
- High quality of evidence: very confident that the true effect lies close to that of the estimate of the effect.
- Moderate quality of evidence: moderately confident in the effect estimate and the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
- Low quality of evidence: confidence in the effect estimate is limited and the true effect may be substantially different from the estimate of the effect.
- Very low quality of evidence: little confidence in the effect estimate and the true effect is likely to be substantially different from the estimate of effect (37).
4 Results:
4.1 Study selection:
Figure 1 shows the detailed screening process. The initial search resulted in 79 studies. 18 of these were considered relevant by title. After the abstract and whole studies were read through six studies remained and their methodological quality was assessed. Two studies were excluded due to high risk of bias-evaluation and therefore four studies were included in the systematic review.
Figure 1: PRISMA Study flow diagram
4.2 Methodological quality/Risk of bias assessment:
One of the included articles was of low risk. Three articles were judged to be of some concern and two studies (27, 30) were of high risk and were therefore excluded. One of the studies that were judged to be of high risk of bias (27) and therefore was excluded was due to lack of information about bias in the measurement of the outcome; domain four. The other study that was judged to be of high risk (30) was due to missing p-values (domain five; bias in selection of reported result). The whole RoB2 evaluation is presented in Appendix F.
Figure 2: RoB2 overview
4.3 Description of the included studies:
Of the four included studies, Madsen et al (2018) compared strength training with ergonomic advice and posture correction (26). Alvarés-Melcón et al (2016) compared physical training, posture correction and relaxation compared to relaxation alone (28). The study by Van Ettekoven & Lucas (2006) compared physiotherapy with and without the addition of craniocervical training (29) and the study by Sertel et al (2017) compared aerobic exercise with body awareness and a control group (31) (Table 1).
4.4 Outcome pain intensity:
The study by Madsen et al (2018) found no significant difference regarding pain intensity when strength training was compared with ergonomic advice and posture correction (26). The study by Álvarez-Melcón et al (2016) found that physical training, posture correction and relaxation compared with relaxation alone had a significant improvement regarding pain intensity (28). Van Ettekoven et al (2006) compared physiotherapy with the addition of craniocervical training with physiotherapy alone. They found that physiotherapy with the addition of craniocervical training seems to be more effective than physiotherapy alone in the long term when it comes to pain intensity (29). The study by Sertel et al (2017) concluded that aerobic exercise and body awareness training was better compared to a control group regarding pain intensity (31).
4.5 Outcome headache frequency:
The study by Madesen et al (2018), found no significant difference regarding headache frequency when strength training was compared with ergonomic advice and posture correction (26). The study by Álvarez-Melcón et al (2016), found that physical training, posture correction and relaxation compared with relaxation alone, had a significant
improvement regarding headache frequency in the long term at 12 weeks follow up but not at 4 weeks (28). The study by Van Ettekoven compared physiotherapy with the addition of craniocervical training with physiotherapy alone and found that physiotherapy with the addition of craniocervical training seems to be more effective than physiotherapy alone in the long term when it comes to headache frequency (29).
Table 1: description of the result in the included studies.
Article Intervention Control
Outcome pain
Outcome frequency
Treatment
duration Followup Mean + SD pain Result Pain
Improvement in %
Mean + SD
frequency Result frequency
Improvement in %
Madsen 2018
Strength training
Ergonomic &
posture NRS 0-10 Days/month 10 weeks
12 weeks after intervention ended
Intervention:
Baseline: 4.4 (1.19) 22 weeks: 3.7 (1.06) Control:
Baseline: 3.7 (1.29) 22 weeks: 4 (1.06)
No significant difference was seen between the groups regarding pain intensity
Intervention:
-15,9%
Control:
+8.1%
Intervention:
Baseline: 19.6 (7.43) 22 weeks: 14.8 (5.70) Control:
Baseline: 17.5 (7.43) 22 weeks: 14.7 (5.70)
No significant difference was seen between the groups regarding headache frequency
Intervention:
-24,5%
Control:
-16.0%
Àlvarez 2016
Physical training + posture +
relaxation Relaxation VAS 0-10 Days/month
4 weeks + 12week (reduced frequency)
4 weeks and 12 weeks after intervention started
Intervention:
Baseline: 5.82 (1.26) 4 weeks: 4.58 (1.53) 16 weeks: 4.23 (1.66) Control:
Baseline: 5.57 (1.32) 4 weeks: 5.19 (1.50) 16 weeks: 4.96 (1.59)
There was a significant difference between the groups regarding pain intensity both at post-treatment (p=0.015) and at follow up (p=0.006)
Intervention:
-27,3%
Control:
-11.0%
Intervention:
Baseline: 12.96 (4.75) 4 weeks: 9.10 (3.57) 16 weeks: 7.14 (3.50) Control:
Baseline: 12.71 (4.07) 4 weeks: 10.25 (3.88) 16 weeks: 8.64 (3.59)
There was a significant difference between the groups regarding headache frequency at follow up (p=0.01) but not at post-intervention (4 weeks) measures (p=0.06)
Intervention:
-44,9%
Control:
-32%
Van Ettekoven 2006
Physiotherapy and
craniocervical
training Physiotherapy NRS 0-10 Days/week 6 weeks
6 weeks and 6 months after intervention started
Intervention:
Baseline 5.72 (1.43) 6 weeks 3.22 (2.34) 6 months: 2.52 (2.14) Control:
baseline: 5.86 (1.84), 6 weeks: 3.32 (2.34) 6 months: 4.44 (2.14)
There was a significant difference between the groups at the 6 month follow up (p=0.001) but not at the 6 weeks follow up (p=0.95)
Intervention:
-55,9%
Control:
-24,9%
Intervention:
Baseline: 5.59 (1.7) 6 weeks: 1.79 (1.2) 6 months: 1.64 (1.8) Control:
Baseline: 4.86 (1.79) 6 weeks: 2.0 (1.2) 6 months: 2.86 (1.8)
There was a significant difference between the groups at the 6 month follow up (p=0.0001) but not at the 6 weeks follow up (p=0.061)
Intervention:
-70,6%
Control:
-41,1%
Sertel 2017
Aerobic exercise
Body awareness/
control group VAS 0-10 6 weeks
6 weeks after the beginning of the study
Intervention:
Baseline: 6.10 (1.02) 6 weeks: 3.00 (1.28) Control:
Baseline: 5.90 (0.71) 6 weeks: 5.65 (0.74)
There was a significant difference between the groups after intervention regarding pain intensity (p=0.00)
Intervention:
-50,8%
Control:
-4,2%
5 Meta-analysis:
5.1 Pain intensity:
Four studies researched the intervention training for the outcome pain intensity in patients with tension-type headache (Table 1). The pooled number of participants in the included studies were 330. The measuring point selected was the first and the last follow up in all studies. The meta-analysis indicates that training is significantly effective in reducing pain intensity in patients with tension-type headache (Figure 3). This improvement does not reach a clinically important difference (-5,1%).
Figure 3: Forest-plot regarding the outcome pain intensity
5.2 Headache frequency:
Three studies investigated training’s effect on headache frequency in patients with tension-type headache (Table 1). The number of participants in the studies were 290 individuals. The measuring point selected was the first and the last follow up in all studies.
The meta-analysis shows that training is significantly effective in reducing headache
frequency in patients with tension-type headache (Figure 4).This improvement does not reach a clinically important difference (-7.1%).
Figure 4: Forest-plot regarding the outcome headache frequency
6 Quality of evidence/GRADE:
6.1 Pain intensity:
The quality of the evidence in the conducted review and meta-analysis is judged to be moderate quality of evidence regarding the outcome pain intensity (Figure 5). The reason for this GRADE was the risk-of-bias evaluation of the included studies where one study was judged to be of low risk-of bias (26) and three were judged to be of some concern (28, 29, 31). In two of these studies (28, 29) one domain was of some concern whereas three domains were of some concern in the study by Sertel et al (2017) (31).
6.2 Headache frequency:
The quality of the evidence in the conducted review and meta-analysis is judged to be high quality of evidence regarding the outcome headache frequency (Figure 5). The reason for this GRADE was the low risk-of-bias in the study by Madsen et al (2018) (26), and the assessment that the other two studies only had one domain that were of some concern.
Figure 5: GRADE/ quality of evidence
7 Discussion:
The results of this review and meta-analysis shows that training can give an improvement regarding pain intensity and headache frequency in patients with tension-type headache.
These results are in accordance with reviews on exercise’s effect on different pain-conditions where the conclusion is that training is effective in decreasing pain intensity (18, 19, 15, 16, 20, 21, 38). Since there are no other reviews on the subject a comparison to literature in the field of tension-type headache is not possible. There is however a number of meta-analyses that conclude that training is effective in reducing headache frequency (39, 40) and pain intensity (40) in patients with migraine.
The results show that training gives a significant decrease in pain intensity for patients with tension-type headache. There is moderate quality of evidence for this outcome. Even though the result is significant, it does not reach a clinically important difference (-5,1%). Of the included studies, the study by Sertel et al (31) that evaluates aerobic training seems to be more effective than the others. In this study aerobic exercise was compared to a passive control group (the body awareness group wasn’t included in the meta-analysis). The real question is if this intervention is more effective than the others or if parts of this result in fact can be a consequence of the other studies' active control group. The control groups in the other studies got ergonomic advice and posture correction (26), relaxation exercises (28) and physiotherapy (massage, oscillation techniques and posture correction) (29).
Training is effective in improving headache frequency in patients with tension-type headache.
This result is significant and the quality of evidence is high. It does however not reach a clinically important difference (-7.1%). It seems that the intervention in the study by Madsen et al (26) is more effective than in the other two. This might be because the intervention in this study is 10 weeks compared to the other two which have an intervention of 4 and 6 weeks respectively. We know from multiple earlier studies of the effect of exercise that the intervention has to be continuous and proceed for weeks up to months depending on what effect we are interested in measuring (22). Some of the effects of exercise continue to improve over years (22).
Although the results of this review does not reach that of clinically important difference one can not fully state whether this result may be a result of the active control groups of the studies. This may result in a smaller difference between the groups. The result of this review is therefore that the clinical relevance is limited but one can’t fully state that it wouldn’t reach a clinically important difference if the control groups were passive. This needs to be
evaluated in future studies.
Since the consensus about the cause or pathology of tension-type headache is unknown we know very little about the effects of the interventions too. We do however know that exercise, both aerobic and anaerobic, has an effect on many of the possible causes of tension-type headache. Such as: muscles, skeleton, peripheral and central pain modulation just to mention a few (5, 22) (see more in section 1). Perhaps the cause or pathology of episodic and chronic tension-type headache differ and therefore the interventions might have different effects depending on the type of tension-type headache. Some of the included studies conclude that episodic and chronic tension-type headache should be divided and researched separately (26, 29). Since all of the included studies did not make a distinction between episodic and chronic tension-type headache a separate evaluation was not possible in this review. This would however be very interesting in future studies.
When it comes to exercise there is a debate on whether there is a difference between different types of training or whether it in fact can be general and that all exercise has an analgesic effect. There are too few studies that have been made on the subject of patients with
tension-type headache to make a distinction. Therefore the author chose to include all sorts of exercise in this review. There are some reviews made on other pain conditions that conclude that both aerobic and anaerobic exercise is equally effective in reducing pain (23, 41, 42).
7.1 Strengths and limitations:
In order to include the study by Van Ettekoven and Lucas (2006) (29) in the meta-analysis a program on the Revman site was used to calculate the group's SD-value (see more detailed explanation in section 3.7). By doing this you get the same SD-value for both the control and the intervention group, making this calculation somewhat questionable.
When one conducts a review one aims to find all studies that are relevant for inclusion. The studies that were included in this review were conducted in the Netherlands (29), Denmark (26), Spain (28) and Turkey (31). One of the included studies recruited participants from the primary care (29), some from departments from hospitals (26, 31) and one from students at the local university (28). This means that the participants in the meta-analysis might be a heterogeneous group with different backgrounds from different cultures. This may be to this meta-analysis disadvantage.
A limitation of the study is the absence of a hand search. This means that there could exist articles that were not included in the search strategy, but at the same time the search that was conducted is easy to replicate.
A weakness of this study is the lone author. When conducting a systematic review there should always be more than one author. This in order to compare and conduct some of the steps included in a systematic review. When conducting a risk of bias analysis and other methodological considerations for example, there should always be two authors. The lone author was in some ways compensated for by a frequent dialogue with the supervisor of this review.
A strength and a weakness of this review and meta-analysis are the few articles included. The author made the decision to exclude two of the articles because of their high risk of bias. By making this choice the evidence obtained in this review can be of higher strength/certainty and therefore come closer to the truth. The authors judgement is that the excluded studies results are in line with the results of the included studies and therefore inclusion of these would probably not have affected the result of this review.
Another strength of this review is the systematic methodology that has been followed throughout. All of these steps and tools have been used in order to make sure the results of this review and meta-analyses are validated and lie as close to the truth as possible.
7.2 Suggestions for future research
This review comes to the conclusion that training in general is effective in reducing pain intensity and headache frequency in tension type headache. More studies are needed to evaluate/conclude whether all exercise (both aerobic and anaerobic exercise) or certain specific exercises is more effective for patients with tension-type headache. Further, future research would benefit if a distinction between episodic and chronic tension-type headache was made. This in order to conclude whether the evidence and effect of the interventions differ depending on the headache definition. This reviews’ result regarding the clinically important difference may be regarded as inconclusive and this needs to be assessed in future research.
8 Conclusion:
There is moderate quality of evidence that exercise can give a significant reduction regarding pain intensity in patients with tension-type headache. There is high quality evidence that exercise can significantly improve headache frequency in patients with tension-type
headache. Neither of these results reach a clinically important difference. This may be due to the active control groups and needs to be researched further. More studies are needed to be able to evaluate different forms of training and whether episodic and chronic tension type headache can/should be researched and treated differently or not.
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29. Van Ettekoven H, Lucas C. Efficacy of Physiotherapy Including a Craniocervical Training
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Appendix A
Date when the search was last made: 29/1 2021 Search strategy in PubMed:
((tension headache) OR (tension type headache)) AND ((((((((((craniocervical exercise) OR (craniocervical training)) OR ((cervical training) OR (cervical exercise))) OR ((motor control training) OR (motor control exercise))) OR ((neuromuscular training) OR (neuromuscular exercise))) OR ((stabilization training) OR (stabilization exercise))) OR ((pressure
biofeedback unit) OR (pressure biofeedback))) OR ((((cervical flexion) OR (cervical flexors)) OR (cervical extension)) OR (cervical extensors))) OR ((neck training) OR (neck exercise))) OR ((((((((((((exercise) OR (training)) OR (rehabilitation)) OR (exercise therapy)) OR ((general exercise) OR (general training))) OR ((conventional exercise) OR (conventional training))) OR ((traditional exercise) OR (traditional training))) OR ((specific exercise) OR (specific training))) OR ((rehabilitation training) OR (rehabilitation exercise))) OR ((strength training) OR (strength exercise))) OR ((resistance training) OR (resistance exercise))) OR (((aerobic exercise) AND (aerobic therapy)) AND (aerobic training))))
Filter: RCT and published after 2004
Search in Cinahl gave no further relevant articles.
Search in WebOfScience gave 8 more relevant articles which were read and excluded due to not fulfilling the review’s PICO.
Appendix B
Of importance for the field of physiotherapy:
Physiotherapists have a unique knowledge of how and why movement is of importance for the individual. This is why it is very important to continuously research the field of
movement as an intervention for different types of pain conditions and diseases. It is important to fill the gaps of knowledge where no research or reviews on the subject have been made. A systematic review on training for patients with tension-type headache has, to the author's knowledge, never been made before. So therefore this review is of importance for the field of physiotherapy.
Of importance for the field of orthopedic manual therapy:
Since patients with headache are a common patient within the physiotherapy practice it is important for us to be able to accurately diagnose and treat these patients. Our choice of treatment should of course be based on the patient's history and our clinical examination. To be able to offer the patient the best treatment, we need to know the evidence for different treatment options. This is why there is a need for this systematic review.
Orthopedic manual therapy is a broad field for the management of musculoskeletal dysfunctions. Our treatment is based on clinical reasoning and we opt for either manual techniques or exercises or a combination of both. When it comes to patients with tension-type headache the field of manual therapy is already researched. When it comes to training for patents with tension-type headache the evidence is lacking, and there’s no systematic review to date.
Importance:
I hope that this review will conclude if training in patients with tension-type headache can be a good treatment to decrease days with headache and pain intensity in patients with
tension-type headache.
Appendix C Declarations:
Ethics: An ethical consideration that was important in this review was that all studies that were relevant for inclusion were included no matter the result of the study. By using a systematic methodology in all steps conducted in this review and meta-analysis the risk of bias because of the author is minimized. The included studies in this review must be made in accordance with the ethical standards of the Helsinki Declaration and therefore have an ethical approval and written or oral consent. According to the Helsinki declaration the patient’s best must always be a priority and autonomy, integrity and protection of personal information is vital. The intervention in the included studies does not mean any harm or risk for the patient. There is always a risk of not offering the best treatment to the participants in a control group in a study. A way to get around this is to offer the best available treatment after the study’s over. The Helsinki declaration also states that the studies need to declare if there’s any conflict of interest, the economics behind the study and what institution the authors of the study belong to (43). In order to make sure this has been done in the included studies, a risk of bias evaluation was made. One subject addressed in the cochrane handbook for systematic reviews (31, 32) is that of equity. Some of the included studies in this review included
patients from a university and different health centers in different countries. Depending on that specific country's healthcare system the included patients may only be the once living in a specific area or of a specific socioeconomic status. This is of course something that should be noted and that the institutions that conduct scientific studies should try to avoid.
Acknowledgements:
The supervisor Peter Michaelson: assistant professor, Med Dr, registered physiotherapist
Competing interest:
The author declares that there are no conflicting interests.
Founding:
The study had no founding
Appendix D
Journal: Cephalalgia
These guidelines have been followed throughout this review.
To mention a few of the guidelines they state how many words that are allowed in the
abstract (200 words) and in the whole article (4000 words). It also states the formatting that’s to be used, reference system (Vancouver) and they state that PRISMA has to be used and followed throughout all reviews and meta-analyses that they publish.
See the whole manuscript submission guidelines:
https://journals.sagepub.com/author-instructions/CEP
Appendix E
PRISMA 2020 Main Checklist
TITLE
Title 1 Identify the report as a systematic review. Title
ABSTRACT
Abstract 2 See the PRISMA 2020 for Abstracts checklist
INTRODUCTIO N
Rationale 3 Describe the rationale for the review in the context of existing knowledge. Section 1 Objectives 4 Provide an explicit statement of the objective(s) or question(s) the review addresses. Section 2 METHODS
Eligibility criteria 5 Specify the inclusion and exclusion criteria for the review and how studies were grouped for the syntheses. Section 3.2 and 3.4
Information
sources 6 Specify all databases, registers, websites, organisations, reference lists and other sources searched or consulted
to identify studies. Specify the date when each source was last searched or consulted. Section 3.3 and Appendix
A
Search strategy 7 Present the full search strategies for all databases, registers and websites, including any filters and limits used. Appendix A
Selection process 8 Specify the methods used to decide whether a study met the inclusion criteria of the review, including how many reviewers screened each record and each report retrieved, whether they worked independently, and if applicable, details of automation tools used in the process.
Section 3.3 and 3.6
Data collection process
9 Specify the methods used to collect data from reports, including how many reviewers collected data from each report, whether they worked independently, any processes for obtaining or confirming data from study investigators, and if applicable, details of automation tools used in the process.
Section 3.6
Data items 10a List and define all outcomes for which data were sought. Specify whether all results that were compatible with each outcome domain in each study were sought (e.g. for all measures, time points, analyses), and if not, the methods used to decide which results to collect.
Section 3.2
10b List and define all other variables for which data were sought (e.g. participant and intervention characteristics, funding sources). Describe any assumptions made about any missing or unclear information.
Section 3.2
Study risk of bias
assessment 11 Specify the methods used to assess risk of bias in the included studies, including details of the tool(s) used, how many reviewers assessed each study and whether they worked independently, and if applicable, details of automation tools used in the process.
Section 3.5
Effect measures 12 Specify for each outcome the effect measure(s) (e.g. risk ratio, mean difference) used in the synthesis or
presentation of results. Section 3.6
Synthesis
methods 13a Describe the processes used to decide which studies were eligible for each synthesis (e.g. tabulating the study
intervention characteristics and comparing against the planned groups for each synthesis (item 5)). Section 3.7
13b Describe any methods required to prepare the data for presentation or synthesis, such as handling of missing summary statistics, or data conversions.
Section 3.7
13c Describe any methods used to tabulate or visually display results of individual studies and syntheses. Table 1
13d Describe any methods used to synthesize results and provide a rationale for the choice(s). If meta-analysis was performed, describe the model(s), method(s) to identify the presence and extent of statistical heterogeneity, and software package(s) used.
Section 3.1 and 3.7
13e Describe any methods used to explore possible causes of heterogeneity among study results (e.g. subgroup
analysis, meta-regression). -
13f Describe any sensitivity analyses conducted to assess robustness of the synthesized results. Section 3.1 and 3.8
Reporting bias
assessment 14 Describe any methods used to assess risk of bias due to missing results in a synthesis (arising from reporting
biases). Section 3.5
and 3.8
Certainty assessment
15 Describe any methods used to assess certainty (or confidence) in the body of evidence for an outcome. Section 3.7 and 3.8 RESULTS
Study selection 16a Describe the results of the search and selection process, from the number of records identified in the search to
the number of studies included in the review, ideally using a flow diagram. Section 4.1 and Figure
1
16b Cite studies that might appear to meet the inclusion criteria, but which were excluded, and explain why they
were excluded. Figure 1
Study characteristics
17 Cite each included study and present its characteristics. Section 4.3
Risk of bias in
studies 18 Present assessments of risk of bias for each included study. Section 4.2
Results of
individual studies 19 For all outcomes, present, for each study: (a) summary statistics for each group (where appropriate) and (b) an
effect estimate and its precision (e.g. confidence/credible interval), ideally using structured tables or plots. Table 1
Results of syntheses
20a For each synthesis, briefly summarise the characteristics and risk of bias among contributing studies. Section 4.2
20b Present results of all statistical syntheses conducted. If meta-analysis was done, present for each the summary estimate and its precision (e.g. confidence/credible interval) and measures of statistical heterogeneity. If comparing groups, describe the direction of the effect.
Section 5
20c Present results of all investigations of possible causes of heterogeneity among study results. -
20d Present results of all sensitivity analyses conducted to assess the robustness of the synthesized results. Section 6
Reporting biases 21 Present assessments of risk of bias due to missing results (arising from reporting biases) for each synthesis
assessed. Section 6
Certainty of
evidence 22 Present assessments of certainty (or confidence) in the body of evidence for each outcome assessed. Section 6
DISCUSSION
Discussion 23a Provide a general interpretation of the results in the context of other evidence. Section 7
23b Discuss any limitations of the evidence included in the review. Section 7.1
23c Discuss any limitations of the review processes used. Section 7.1
23d Discuss implications of the results for practice, policy, and future research. Section 7, 7.1 and 8
OTHER INFORMATION
Registration and
protocol 24a Provide registration information for the review, including register name and registration number, or state that the
review was not registered. -
24b Indicate where the review protocol can be accessed, or state that a protocol was not prepared. -
24c Describe and explain any amendments to information provided at registration or in the protocol. -
Support 25 Describe sources of financial or non-financial support for the review, and the role of the funders or sponsors in the review.
Appendix C
Competing
interests 26 Declare any competing interests of review authors. Appendix
C
Availability of data, code and other materials
27 Report which of the following are publicly available and where they can be found: template data collection forms; data extracted from included studies; data used for all analyses; analytic code; any other materials used in the review.
-
PRIMSA Abstract Checklist
Topic No
. Item Reported
? TITLE
Title 1 Identify the report as a systematic review. Yes
BACKGROUN D
Objectives 2 Provide an explicit statement of the main objective(s) or question(s) the review addresses. Yes METHODS
Eligibility
criteria 3 Specify the inclusion and exclusion criteria for the review. Yes
Information sources
4 Specify the information sources (e.g. databases, registers) used to identify studies and the date when each was last searched.
Yes
Risk of bias 5 Specify the methods used to assess risk of bias in the included studies. Yes
Synthesis of 6 Specify the methods used to present and synthesize results. Yes
RESULTS
Included studies 7 Give the total number of included studies and participants and summarise relevant characteristics of studies. Yes
Synthesis of
results 8 Present results for main outcomes, preferably indicating the number of included studies and participants for each.
If meta-analysis was done, report the summary estimate and confidence/credible interval. If comparing groups, indicate the direction of the effect (i.e. which group is favoured).
Yes
DISCUSSION
Limitations of
evidence 9 Provide a brief summary of the limitations of the evidence included in the review (e.g. study risk of bias,
inconsistency and imprecision). Yes
Interpretation 10 Provide a general interpretation of the results and important implications. Yes OTHER
Funding 11 Specify the primary source of funding for the review. No
Registration 12 Provide the register name and registration number. No
From: Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. MetaArXiv. 2020, September 14. DOI: 10.31222/osf.io/v7gm2. For more information, visit:www.prisma-statement.org
2
Appendix F
Unique ID Madsen 2018 Study ID 1 Assessor Elin Rundström
Ref or Label ESTTH Aim assignment to intervention (the
'intention-to-treat' effect)
Experimental Strenght training Comparator Ergonomic & posture Source Journal article(s); Trial protocol
Outcome Pain intensity Results Table 2 Weight 1
Domain Signalling question Response Comments
Bias arising from the randomization process
1.1 Was the allocation sequence random? Y Random sequence generator. They
were grouped by the physiotherapist on the first day.
1.2 Was the allocation sequence concealed until participants were enrolled and assigned to interventions?
PY
1.3 Did baseline differences between intervention groups suggest a problem with the randomization process?
N
Risk of bias judgement Low
Bias due to deviations from intended interventions
2.1.Were participants aware of their assigned intervention during the trial? Y Knew of the two groups. Both were presented as equally effective interventions.
Physiotherapist had to know but was blinded for the result.
2.2.Were carers and people delivering the interventions aware of participants' assigned intervention during the trial?
Y
2.3. If Y/PY/NI to 2.1 or 2.2: Were there deviations from the intended intervention that arose because of the experimental context?
NI
2.4 If Y/PY to 2.3: Were these deviations likely to have affected the outcome? NA 2.5. If Y/PY/NI to 2.4: Were these deviations from intended intervention balanced between groups? NA
2.6 Was an appropriate analysis used to estimate the effect of assignment to intervention? Y However both ITT and PP was conducted
2.7 If N/PN/NI to 2.6: Was there potential for a substantial impact (on the result) of the failure to analyse participants in the group to which they were randomized?
NA
Risk of bias judgement Low
Bias due to missing outcome data
3.1 Were data for this outcome available for all, or nearly all, participants randomized? Y ITT and PP was conducted
Mean values of the group was used to substitute for missing values.
3.2 If N/PN/NI to 3.1: Is there evidence that result was not biased by missing outcome data? NA 3.3 If N/PN to 3.2: Could missingness in the outcome depend on its true value? NA 3.4 If Y/PY/NI to 3.3: Is it likely that missingness in the outcome depended on its true value? NA
Risk of bias judgement Low
Bias in
measurement of the outcome
4.1 Was the method of measuring the outcome inappropriate? N
4.2 Could measurement or ascertainment of the outcome have differed between intervention groups? N
4.3 Were outcome assessors aware of the intervention received by study participants? NI Doesn't say 4.4 If Y/PY/NI to 4.3: Could assessment of the outcome have been influenced by knowledge of
intervention received?
N
4.5 If Y/PY/NI to 4.4: Is it likely that assessment of the outcome was influenced by knowledge of intervention received?
NA
Risk of bias judgement Low
Bias in selection of the reported result
5.1 Were the data that produced this result analysed in accordance with a pre-specified analysis plan that was finalized before unblinded outcome data were available for analysis?
PY The trial-protocol doesn't contain info about the statistical analysis plan.
5.2 ... multiple eligible outcome measurements (e.g. scales, definitions, time points) within the outcome domain?
PN
5.3 ... multiple eligible analyses of the data? PN
Risk of bias judgement Low
Unique ID Andersen 2017 Study ID 2 Assessor Elin Rundström
Ref or Label ERTH Aim assignment to intervention (the
'intention-to-treat' effect)
Experimental Strenght training Comparator No intervention Source Journal article(s)
Outcome Pain Results Table 2 and 3 Weight 1
Domain Signalling question Response Comments
Bias arising from the randomization process
1.1 Was the allocation sequence random? NI Doesn't say how the randomization
process was carried out.
1.2 Was the allocation sequence concealed until participants were enrolled and assigned to interventions?
NI
1.3 Did baseline differences between intervention groups suggest a problem with the randomization process?
N
Risk of bias judgement Some concerns
Bias due to deviations from intended interventions
2.1.Were participants aware of their assigned intervention during the trial? NI 2.2.Were carers and people delivering the interventions aware of participants' assigned intervention
during the trial?
NI
2.3. If Y/PY/NI to 2.1 or 2.2: Were there deviations from the intended intervention that arose because of the experimental context?
Y 26 participants change work location and therefore group.
2.4 If Y/PY to 2.3: Were these deviations likely to have affected the outcome? NI
2.5. If Y/PY/NI to 2.4: Were these deviations from intended intervention balanced between groups? PN 26 of 344 2.6 Was an appropriate analysis used to estimate the effect of assignment to intervention? Y
2.7 If N/PN/NI to 2.6: Was there potential for a substantial impact (on the result) of the failure to analyse participants in the group to which they were randomized?
NA 26 out of 344 shouldn’t have a
substantial impact.
Risk of bias judgement Some concerns
Bias due to missing outcome data
3.1 Were data for this outcome available for all, or nearly all, participants randomized? Y
3.2 If N/PN/NI to 3.1: Is there evidence that result was not biased by missing outcome data? NA 229 lost to follow-up 3.3 If N/PN to 3.2: Could missingness in the outcome depend on its true value? NA
3.4 If Y/PY/NI to 3.3: Is it likely that missingness in the outcome depended on its true value? NA
Risk of bias judgement Low
Bias in
measurement of the outcome
4.1 Was the method of measuring the outcome inappropriate? PN
4.2 Could measurement or ascertainment of the outcome have differed between intervention groups? N 4.3 Were outcome assessors aware of the intervention received by study participants? NI 4.4 If Y/PY/NI to 4.3: Could assessment of the outcome have been influenced by knowledge of
intervention received?
NI No info if the patients knew about the different interventions.
4.5 If Y/PY/NI to 4.4: Is it likely that assessment of the outcome was influenced by knowledge of intervention received?
NI
Risk of bias judgement High
Bias in selection of the reported result
5.1 Were the data that produced this result analysed in accordance with a pre-specified analysis plan that was finalized before unblinded outcome data were available for analysis?
NI No trial protocol was found
5.2 ... multiple eligible outcome measurements (e.g. scales, definitions, time points) within the outcome domain?
NI
5.3 ... multiple eligible analyses of the data? NI
Risk of bias judgement Some concerns
