Risk of bias in chiropractic mixed methods research: a secondary analysis of a meta-epidemiological review.

Objective: To examine the risk of bias in chiropractic mixed methods research.
Methods: We performed a secondary analysis of a meta-epidemiological review of chiropractic mixed methods studies. We assessed risk of bias with the Mixed Methods Appraisal Tool (MMAT) and used generalized estimating equations to explore factors associated with risk of bias.
Results: Among 55 eligible studies, a mean of 62% (6.8 [2.3]/11) of MMAT items were fulfilled. In our adjusted analysis, studies published since 2010 versus pre-2010 (adjusted odds ratio [aOR] = 2.26; 95% confidence interval [CI], 1.39 to 3.68) and those published in journals with an impact factor versus no impact factor (aOR = 2.21; 95% CI, 1.33 to 3.68) were associated with lower risk of bias.
Conclusion: Our findings suggest opportunities for improvement in the quality of conduct among published chiropractic mixed methods studies. Author compliance with the MMAT criteria may reduce methodological bias in future mixed methods research.
Competing Interests: The authors have no disclaimers, competing interests, or sources of support or funding to report in the preparation of this manuscript. Dr. Emary is supported by research grants from McMaster University, the NCMIC Foundation, and the Canadian Chiropractic Research Foundation outside of the submitted work. Dr. Busse is funded, in part, by a Canada Research Chair in the prevention and management of chronic pain from the Canadian Institutes of Health Research Fellowship Award.
(© JCCA 2022.)