Methodological quality of systematic reviews on treatments for Parkinson’s disease: A cross-sectional study

Article type
Authors
Zhang Y1, Lin Y2, Zhong CC1, Ho FF3, Wu IX2, Mao C4, Yang X5, Chung VCH6
1Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Shatin, Hong Kong
2Xiangya School of Public Health, Central South University
3School of Chinese Medicine, The Chinese University of Hong Kong
4Department of Epidemiology, School of Public Health, Southern Medical University
5State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine
6Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Shatin, Hong Kong; School of Chinese Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
Abstract
Background:
Systematic reviews (SRs) with high methodological quality can provide the best evidence for clinical practice. However, the methodological quality of SRs on treatments for Parkinson’s disease has not been evaluated comprehensively.

Objectives:
The study aims to assess the methodological quality of a representative sample of SRs on treatments for Parkinson’s disease.

Methods:
To obtain potentially eligible SRs, a literature search was conducted in four international databases including the Cochrane Database of Systematic Reviews, MEDLINE, Embase and PsycINFO from January 2016 to December 2021. A predesigned questionnaire was used to extract the bibliographical characteristics of the included SRs. The Assessing the Methodological Quality of Systematic Reviews (AMSTAR 2) tool was used to assess the methodological quality of SRs. Factors of methodological quality were explored using multivariable regression analyses.

Results:
A total of 119 eligible SRs were included and appraised in this study. Only one SR (0.8%) was appraised as being of high overall methodological quality. Four (3.4%) and seven (5.9%) SRs were of moderate and low overall methodological quality, respectively. Among the appraised SRs, only 3 (2.5%) used a comprehensive literature search strategy, 11 (9.2%) provided a list of excluded studies with justifications for exclusion and 4 (3.4%) reported the sources of funding for the studies included in the review. Cochrane SRs and SRs published in journals with higher impact factors had relatively higher overall methodological quality.

Conclusions:
This study demonstrated that SRs on Parkinson’s disease treatments have relatively low methodology quality. To enhance the methodological quality of SRs, future reviews should establish and register a priori protocol, conduct a comprehensive literature search, provide a list of excluded studies with justifications for exclusion and report on the sources of funding for the studies included in the review.

Patient, public and/or healthcare consumer involvement: Not applicable.