Methodological quality of the review: Low confidence

Author: Newman-Casey PA, Weizer JS, Heisler M, Lee PP, Stein JD

Geographical coverage: Not reported

Sector: Glaucoma medication

Sub-sector: Glaucoma medication adherence

Equity focus: None specified

Review type: Effectiveness review

Quantitative synthesis method: Narrative synthesis

Qualitative synthesis method: Not applicable

Background: Glaucoma is one of the most common causes of blindness globally. Adherence to prescribed glaucoma medications is often poor, and proper adherence can be challenging for patients.

Objectives: This review focused on published trials that tested the effect of educational intervention on glaucoma medication adherence. The specific objectives were to evaluate the interventions based on quality, efficacy and the extent to which they are grounded in evidence-based Health Behaviour Theory.

Main findings: In this systematic review, eight studies were included (four randomised controlled trials [RCTs] and four observational studies). Two out of the four RCTs scored 2/5 using the Jaded score as there was no description of those not completing follow-up or how the assessors of the outcome were masked to the treatment arm. The Jadad score for one RCT trial was 3/5 as there was no description of how the assessors of the outcome were masked to the treatment arm; and one RCT trial’s Jadad score was 5/5 as the study was appropriately randomised. The subjects lost to follow-up were appropriately described and the assessment of adherence utilised pharmacy claims data, so the assessor was effectively masked to the measurement of the outcome. Observational studies were not appraised.

Overall, authors noted that five out of eight (63%) of the reviewed studies revealed a statistically significant improvement in glaucoma medication adherence after educational interventions, and two others (25%) demonstrated a trend towards an improvement in adherence that was not statistically significant. One study (12%) of patients who already had a relatively high baseline adherence level showed no improvement after an educational intervention. In addition, the types of educational interventions utilised in each study were very different from one another; therefore, authors noted that it was difficult to determine which specific aspects of the educational interventions had the most impact on medication adherence.

Authors also suggested that more rigorous studies grounded in Health Behaviour Theory with adequately powered samples and longer follow-up are required.

Methodology: The following databases were searched for relevant studies: PUBMED, CINAHL and EMBASE. Specific search terms were used and no language restriction was applied. Identification of studies and quality appraising were conducted by two independent reviewers. Data extraction from relevant studies was done by one reviewer and independently checked by another reviewer. The Jadad score was used to judge the quality of RCTs, it’s not clear however if the observational studies were critically appraised.

Authors used a narrative approach to synthesise evidence of included studies.

Applicability/external validity: No methods were used either to assess the applicability/external validity of the results or to discuss how generalizable the results are.

Geographic focus: Geographical focus of included studies was not reported.

Summary of quality assessment: Overall there is low confidence in the conclusions about the effects of this study as major limitations were identified. Authors conducted a narrative synthesis of the findings, which seemed appropriate due to the diversity of studies. Two reviewers independently screened studies for inclusion. The data was abstracted from the articles by one researcher and independently verified by a second researcher. To critically appraise each RCT, authors used the Jadad score, however observational studies were critically appraised. In addition, authors did not conduct a thorough search of the literature to ensure that publication bias was avoided.