Supplementary Material for: Identifying Potentially Modifiable Factors Associated with Treatment Non-Adherence in Paediatric Growth Hormone Deficiency: A Systematic Review

Background: Despite the developments of recombinant growth hormone (rhGH) treatment and the benefits in long-term clinical health outcomes, evidence has shown that many children with growth hormone deficiency (GHD) still fail to achieve their target adult height. Suboptimal outcomes have been largely attributed to treatment non-adherence. Methods: A search of 11 electronic databases was undertaken to identify relevant articles, published in English, between 1985 and 2018. Additional search strategies included hand-searching topic review articles to identify eligible studies. Articles were screened against the inclusion eligibility criteria and data on sample characteristics, study design, outcomes, and key findings was extracted. The results were narratively synthesised and categorised using the COM-B theoretical framework. Results: Twenty-one full-text articles were assessed for eligibility, of which 6 articles met the inclusion criteria. The prevalence of non-adherence in the included studies varied from 7 to 71%. Potentially modifiable factors associated with rhGH non-adherence were categorised within the COM-B framework; key factors included: a lack of knowledge and understanding of the condition and treatment, discomfort and pain associated with injections, and the quality of the healthcare professional-patient relationship. Conclusion: This review highlights the scope of the adherence problem evident amongst the paediatric GHD population and in addition presents the wide range of potentially modifiable factors that explain this health-related behaviour.