Summary: In a single-site Iranian quasi-experimental study of 100 older adults (aged 60 years and above) with type 2 diabetes, a six-session programme based on the Information-Motivation-Behavioral Skills (IMB) model raised self-reported medication adherence scores from 16.92 to 19.76 (p<0.001; Cohen’s d 1.15) against routine care. The largest gains were seen in the Information component, while Subjective Norms did not change meaningfully.
PICO Summary
| Element | Detail |
|---|---|
| Population | 100 community-dwelling older adults aged 60 years and above with type 2 diabetes; single-site quasi-experimental study, Kermanshah, Iran, 2024. |
| Intervention | Six 40-minute group education sessions over six weeks based on the Information-Motivation-Behavioral Skills (IMB) model (n=50). |
| Comparison | Routine diabetes care with no structured IMB education (n=50). |
| Outcome | Self-reported medication adherence score rose from 16.92 to 19.76 in the intervention arm (p<0.001; Cohen’s d 1.15), with minimal change in controls. IMB components: Information d 1.3 (mean change 3.84, p<0.001), Self-efficacy d 0.67, Attitude d 0.65, Subjective Norms d 0.11 (not significant). No 95% confidence intervals, between-group adjusted estimates, ARR or NNT were reported; the adherence outcome was continuous and self-reported. |
IMB model for medication adherence
Quasi-experimental · type 2 diabetes · 6 weeks
A six-session IMB education programme raised self-reported medication adherence from 16.92 to 19.76 (Cohen's d 1.15) versus minimal change in controls, but the outcome was self-reported in a single-site open-label study, so the signal needs replication with objective measures.
Expert Commentary
This study reports that a brief, theory-based education programme was associated with improved self-reported medication adherence in older adults with type 2 diabetes, with a very large within-group effect size for adherence and for the Information domain. The verdict is that the signal is encouraging but the certainty is low. The design is quasi-experimental and the intervention is inherently open-label, so participants and educators knew their allocation, a setup that tends to inflate self-reported behavioural outcomes through social desirability and expectation. The principal limitation that should temper enthusiasm is the outcome measure itself: adherence was captured by questionnaire rather than by pill counts, pharmacy refill data, or glycaemic endpoints such as HbA1c, so the reported gains may not translate into objective medication-taking or better glucose control. Effect sizes above one in a single-site sample of 100 are also implausibly strong for an educational nudge and warrant external replication before being taken at face value. Can I use this with my patients? Not yet as a defined protocol, though the underlying principle, that structured information and motivational support help older patients take medicines, is sound and low-risk to apply informally. I would welcome a larger, multi-centre trial with objective adherence measures and HbA1c before recommending the IMB programme as standard practice.
References
Mirzaei-Alavijeh M, Yarmoradi S, Khashij S, Jalilian F. Application of the information-motivation-behavioral skills model to improve medication adherence among older adults with type 2 diabetes: findings from a quasi-experimental study in Kermanshah, Iran. BMC Geriatr. 2025;25(1):328. doi:10.1186/s12877-025-06000-w