Measurement of adherence in bariatric surgery: a systematic review

After bariatric surgery, rates of adherence to behavioral recommendations, including attending regular appointments and following specific dietary, physical activity, and vitamin use recommendations, tend to be highly variable across studies. Lack of consistency in measurement of adherence is a likely contributor to this variability, making it challenging to determine the prevalence and impact of nonadherence in this population. PubMed was searched for articles measuring behavioral adherence or compliance in patients after bariatric surgery, resulting in 85 articles. Articles were reviewed for the definition and measurement of adherence in each area (appointment attendance, as well as dietary, physical activity, and vitamin use adherence), and on the use and reporting of recommended adherence measurement strategies. Over half of the articles measured adherence to appointment attendance. Significant variability was found across adherence definitions and measurement methods, and use of recommended adherence measurement strategies was poor. Adherence was mostly commonly measured via self-report (either verbal or written) using cutoffs for adherent versus nonadherent behavior. Over half of studies assessed adherence up to ≥2 years postsurgery. Recommendations for ways to improve adherence measurement in patients who have had bariatric surgery are outlined.