A 7-Step Guideline for Qualitative Synthesis and Meta-Analysis of Observational Studies in Health Sciences

Marija Glisic; Peter Francis Raguindin; Armin Gemperli; Petek Eylul Taneri; Dante Jr Salvador; Trudy Voortman; Pedro Marques Vidal; Stefania I Papatheodorou; Setor K Kunutsor; Arjola Bano; John P A Ioannidis; Taulant Muka

doi:10.3389/phrs.2023.1605454

A 7-Step Guideline for Qualitative Synthesis and Meta-Analysis of Observational Studies in Health Sciences

Public Health Rev. 2023 May 16:44:1605454. doi: 10.3389/phrs.2023.1605454. eCollection 2023.

Authors

Marija Glisic^{1

2}, Peter Francis Raguindin^{1

2

3

4}, Armin Gemperli^{2

5}, Petek Eylul Taneri⁶, Dante Jr Salvador^{1

3}, Trudy Voortman^{7

8}, Pedro Marques Vidal⁹, Stefania I Papatheodorou¹⁰, Setor K Kunutsor^{11

12}, Arjola Bano^{1

13}, John P A Ioannidis^{14

15

16

17}, Taulant Muka^{1

17

18}

Affiliations

¹ Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland.
² Swiss Paraplegic Research, Nottwil, Switzerland.
³ Graduate School for Health Sciences, University of Bern, Bern, Switzerland.
⁴ Faculty of Health Science and Medicine, University of Lucerne, Lucerne, Switzerland.
⁵ Institute of Primary and Community Care, University of Lucerne, Lucerne, Switzerland.
⁶ HRB-Trials Methodology Research Network, National University of Ireland, Galway, Ireland.
⁷ Department of Epidemiology, Erasmus MC, University Medical Center, Rotterdam, Netherlands.
⁸ Division of Human Nutrition and Health, Wageningen University and Research, Wageningen, Netherlands.
⁹ Department of Medicine, Internal Medicine, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland.
¹⁰ Department of Epidemiology, Harvard TH Chan School of Public Health, Boston, MA, United States.
¹¹ Diabetes Research Centre, University of Leicester, Leicester General Hospital, Leicester, United Kingdom.
¹² Translational Health Sciences, Bristol Medical School, University of Bristol, Southmead Hospital, Bristol, United Kingdom.
¹³ Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
¹⁴ Stanford Prevention Research Center, Department of Medicine, Stanford University School of Medicine, Stanford, CA, United States.
¹⁵ Department of Epidemiology and Population Health, Stanford University School of Medicine, Stanford, CA, United States.
¹⁶ Department of Statistics, Stanford University, Stanford, CA, United States.
¹⁷ Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, United States.
¹⁸ Epistudia, Bern, Switzerland.

Abstract

Objectives: To provide a step-by-step, easy-to-understand, practical guide for systematic review and meta-analysis of observational studies. Methods: A multidisciplinary team of researchers with extensive experience in observational studies and systematic review and meta-analysis was established. Previous guidelines in evidence synthesis were considered. Results: There is inherent variability in observational study design, population, and analysis, making evidence synthesis challenging. We provided a framework and discussed basic meta-analysis concepts to assist reviewers in making informed decisions. We also explained several statistical tools for dealing with heterogeneity, probing for bias, and interpreting findings. Finally, we briefly discussed issues and caveats for translating results into clinical and public health recommendations. Our guideline complements "A 24-step guide on how to design, conduct, and successfully publish a systematic review and meta-analysis in medical research" and addresses peculiarities for observational studies previously unexplored. Conclusion: We provided 7 steps to synthesize evidence from observational studies. We encourage medical and public health practitioners who answer important questions to systematically integrate evidence from observational studies and contribute evidence-based decision-making in health sciences.

Keywords: cohort studies; cross-sectional studies; evidence-based approach; observational study; systematic review and meta-analysis.

Publication types

Review

Grants and funding

PFR and DS received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 801076, through the SSPH+ Global PhD Fellowship Programme in Public Health Sciences (GlobalP3HS) of the Swiss School of Public Health.