Effect on the Adherence to Glaucoma Eye Drops by Improving Patient Understanding and Using a Tele-reminder System

This is a randomized controlled clinical trial study with patients recruited from the National University Hospital, Singapore who met eligibility criteria and agreed to participate in the study during their regularly scheduled outpatient visits. Written informed consent was obtained after the nature of the study had been fully explained to the patient. Recruitment took place from October 2018 to October 2019. The study received the local Institutional Review Board approval and all procedures are in accordance with the ethical standards as stated in the Helsinki Declaration.

A total of 59 patients were recruited for the study. Subjects were randomised into three groups: control (n=19), card only (n=20), card and tele-reminder (n=20) with an allocation ratio of 1:1:1. (Figure 1). Sample size was calculated based on similar drug adherence studies powered to detect a true difference in adherence rates with power at 80% and alpha at 5% - 20 patients per group were required.

The personalised card was printed by the attending ophthalmologist for the patient via a web accessible software we have developed. The software allowed the reviewing physician to select the medications the patient was prescribed and auto-generate a personalised card that will be sent to the network printer. The card illustrated the patient's eye drop regime in a simple pictorial format using coloured pictures of the eye drop bottles and universally recognised symbols. It can be folded to a compact size of 11cm x 7.5cm to allow patients to carry around in their wallets. This card will be given to patients at the end of their consult and explanation will be provided by the attending physician who will manually tick in the corresponding boxes depending on the frequency of administration.

Patients who were recruited into the group receiving tele-monitoring were contacted via text messages daily by a programmed software at the scheduled time of eye drop administration. They were required to acknowledge the reminder by replying a 'Yes' if they had administered the eyedrop and 'No' if they had not. A nil reply was taken as a 'No'.

Trained research assistants and a medical student administered the pre-implementation baseline adherence questionnaire in-person after informed consent was obtained. The questionnaire included questions on (i) demographics (ii) barriers to adherence and (iii) Morisky adherence scale. The demographic information included age, gender, length of time using glaucoma medications, number of glaucoma medications, educational level, whether they identify the medications by name or colour and who helps with the eye drop instillation. In the second section on barriers to adherence, participants were asked to use a visual analogue scale to rate the importance of 11 commonly cited reasons that make it "hard for patients to take glaucoma eye drops." The visual analog scale had 5 major hatch marks anchored between "strongly disagree" and "strongly agree." In the third section of the questionnaire, participants completed the Morisky Adherence Scale, a validated instrument for measuring self-reported adherence which was targeted for glaucoma medications in this study.

The interventions in both the card and tele-reminder groups were administered for a period of 6 weeks, following which a post-implementation adherence questionnaire was conducted via a telephone call by the same research assistants and medical student. The questionnaire included the same questions on the Morisky adherence scale as per the pre-implementation questionnaire.