How applicable are results of systematic reviews and meta-analyses of health behaviour maintenance? A critical evaluation

Abstract

Objective

To evaluate the practical applicability of systematic reviews and meta-analyses to the maintenance of physical activity or weight loss by assessing methodological and reporting aspects.

Methods

To identify relevant studies a literature search was conducted in MEDLINE, EMBASE, Cochrane Library, PsycINFO, PSYNDEX, Google scholar, and reference lists. Each article was evaluated for methodological quality, operationalization of maintenance, and practicability following the RE-AIM framework and the PRISMA statement.

Results

Twenty-four systematic reviews and meta-analyses were included of which 14 were published in the last four years. There were multiple definitions of maintenance. In addition the instances of redundancy, and neglect of thematic fields are identified. Eighty-seven percent of the reviews showed methodological flaws. The potential practical use of the outcomes was limited.

Conclusion

The applicability of systematic reviews and meta-analyses regarding health behaviour maintenance is limited with regard to reporting, methodology and thematic coverage. For practitioners, synthesis of quantitative and qualitative evidence with theoretical models is lacking.

Introduction

The burden of disease worldwide is largely caused by non-communicable diseases that are preventable by health behaviour change. Physical activity (PA)1, 2 and weight loss3, 4 have been revealed to be of particular importance. Several intervention approaches are known which reliably initiate behaviour change, yet the translation to long-term maintenance of those behaviours has been less successful.5, 6

Existing health behaviour theories and models such as the Health Belief Model,⁷ Theory of Planned Behaviour,⁸ Social Cognitive Theory,⁹ the Transtheoretical Model,¹⁰ and the Self-Determination Theory¹¹ have served for many years as guides to intervention development and delivery. The question of why strategies that facilitate the initiation of behaviour change have failed to produce long-term effects has been addressed by both behavioural interventions and various theoretical concepts. The transtheoretical model, for example, includes different stages of health behaviour change, each of which require different interventions.12, 13 Other models, specifically the health action process approach (HAPA), have focused on the distinct psychological influences and processes during different stages between initiation and maintenance.14, 15, 16

It has been argued that it is important to incorporate theoretical models into interventions for health behaviour initiation and maintenance in order to identify those that are most effective.17, 18 This could facilitate the development of variable frameworks which describe the crucial determinants of long-term effective interventions. In order to facilitate the translation of long-term health behaviour change into practice the evidence has to be continuously aligned with the theories and systematically compared, taking the many existing health behaviour theories, the plethora of methodologically heterogeneous trials, and the complexity of health behaviour into consideration.

Systematic reviews and meta-analyses could help health behaviour interventionists and decision makers to identify those strategies that are most promising for long-term maintenance and thus further bridge the theory-practice gap, particularly in regard to multiple lifestyle interventions. For this purpose, the reviews would need to be methodologically valid, consistent with regard to the underlying concept of maintenance, and comprise the potential of being translated into a regular practice setting. The latter requirement refers to external and ecological validity, which is rarely addressed by randomized controlled trials (RCTs) and therefore frequently disregarded by systematic reviews and meta-analyses, as they normally only comprise evidence from RCTs. A well conducted systematic review applies an objective search strategy to the literature, selects studies by predetermined inclusion and exclusion criteria, and critically appraises and adequately combines the relevant studies. The methodological quality of systematic reviews can be assessed by tools such as the AMSTAR (assessment of multiple systematic reviews) tool.19, 20 In contrast, little research has been conducted on the assessment of a study's potential impact on practice21, 22 or its external validity.²³

This study has three areas of investigation. First, the methodology of systematic reviews and meta-analyses dealing with the maintenance of PA and weight loss should be evaluated. Second, whether there is a consistent definition of long-term maintenance in the literature should be investigated. Third, the practicability of the studies in accordance with the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) statement are examined.