This research project was funded by a grant from the Chief Scientist Office of £224,978 (CZH/4/569), awarded to the research team of Professor Ronan O'Carroll (Stirling), Professor Martin Dennis and Dr Cathie Sudlow (Edinburgh) and Professor Marie Johnston (Aberdeen). The project ran from the 1st December 2009 to 30th June 2012. Dr Julie Chambers was appointed as post-doctoral Research Fellow and was responsible for the day-to-day management and running of the IAMSS trial.

Project Summary

Taking medicines as prescribed is a primary determinant of whether treatments work or not, yet the World Health Organisation estimate that only 50% of patients who suffer from chronic diseases adhere to treatment recommendations. In Scotland non-hospital prescription drugs are costing the health service nearly £1 billion a year, yet patients not taking their pills as directed by doctors (i.e. poor adherence) is a huge clinical problem. In a previous research project (see 'Background' below), O’Carroll and his team found that 30% of stroke patients reported sub-optimal medication adherence, and this was associated with younger age, greater memory impairment, lower beliefs about the benefits of medication, and higher concerns about potential harmful effects of their medication.

In the current project we tested a brief (2 session) intervention aimed at: (a) helping patients establish a better medication-taking routine, and (b) eliciting and modifying any unhelpful beliefs regarding their medication and their stroke. The full study protocol has been published in BMC Neurology and is available here
BMC Neurology 2010, 10:15doi:10.1186/1471-2377-10-15.


The IAMSS project developed out of our previous project, 'Psychological factors which influence adherence to medication in stroke patients'. Two papers have been published from this initial study:

Chambers JA, O'Carroll RE, Hamilton B, Whittaker J, Johnston M, Dennis M & Sudlow S. (2010) Adherence to Medication in Stroke Survivors: A Qualitative Comparison of low and high Adherers. British Journal of Health Psychology 2011; 16: 592-609

O’Carroll RE, Whittaker J, Hamilton B. Johnston M, Sudlow C & Dennis M (2010) Predictors of adherence to secondary preventive medication in stroke patients. Annals of Behavioral Medicine 2011; 41: 383-90



The last patient completed treatment in March 2012 and the final report was submitted to the Chief Scientist Office in August 2012.

Brief results

Sixty-two patients were eligible and agreed to take part in the intervention (31 in each treatment arm). The primary outcome was medication adherence measured objectively over 3 months using MEMS pill containers which electronically record cap openings. We also assessed self-reported adherence; blood pressure; beliefs about illness and medication; and feasibility, ease of understanding, and acceptability of the intervention. Both groups received the same levels of contact over the 3-month period.

According to our study protocol (here), we analysed all patients with data on our main outcome measure i.e. the MEMS pill-bottle. Fifty-eight patients used the pill-bottle and were analysed as allocated: 29 in the brief intervention and 29 in the control group. Fifty-four patients completed treatment.

There was a significant difference between treatment arms over the 3-month period on percentage of doses taken on schedule (Intervention 97% versus Control 87%, 95% CI for difference (0.2-16.2), p=.048). The Intervention group also had a significantly greater increase in self-reported adherence (MARS) from pre-treatment to follow-up (mean difference: 0.61, 95% CI (0.1-1.2), p=.027), and significantly greater reduction in concerns about medication (mean difference: 1.1, 95% CI (0.3-2.3), p=.047). There were no effects of the intervention on blood pressure or beliefs about illness.

There was evidence for a mediation effect of reduction in concerns about medication (from post-treatment to follow-up) and forgetting medication (from pre-treatment to follow-up) on MEMS adherence. In other words, the intervention appeared to have the effect of making patients less concerned about their medication, as well as reducing the frequency of forgetting to take their tablets, both of which, in turn, may have led to increased adherence. We suggest that addressing patients’ concerns about their medication is likely to result in higher adherence by making them less reluctant to take it, whilst encouraging patients to develop plans to aid regular pill-taking can help establish automatic habits, which will make forgetting much less likely.

At the final interview, patients were asked to rate the ease (of understanding or use), acceptability and helpfulness of different elements of the intervention. Most patients agreed that all elements of the intervention were easy to understand, acceptable and helpful.

Conclusions: Our results show that a simple, brief intervention, which is acceptable to patients, increases adherence to anti-hypertensive medication in stroke survivors, over and above mere measurement effect (i.e. use of the electronic pill-bottle) or any effect of increased patient contact. The effect found was equivalent to taking 1 additional dose in 10 within +/- 3 hours of a regular time.

The active part of the intervention took less than 30 minutes and so we believe it could be delivered by trained non-specialists, and may be generalizable to other elderly patients taking multiple medications in a range of healthcare settings.


Main results

O'Carroll RE, Chambers JA, Dennis M, Sudlow C & Johnston M. (2013). Improving Adherence to Medication in Stroke Survivors: A Pilot Randomised Controlled Trial, Annals of Behavioral Medicine, 46 (3), pp. 358-368.

Additional analyses

O'Carroll RE, Chambers JA, Dennis M, Sudlow C & Johnston M. (2014). Improving medication adherence in stroke survivors: Mediators and moderators of treatment effects, Health Psychology, 33 (10), pp. 1241-1250. DOI: http://dx.doi.org/10.1037/hea0000082

Chambers JA, O'Carroll RE, Martin D, Sudlow C & Johnston M. (2014). 'My doctor has changed my pills without telling me': impact of generic medication switches in stroke survivors, Journal of Behavioral Medicine, 37 (5), pp. 890-901. DOI: http://dx.doi.org/10.1007/s10865-013-9550-5

Chambers JA, O'Carroll RE, Dennis M, Sudlow C & Johnston M. (2015). Personal experiences of electronic measurement of medication adherence in elderly stroke survivors, Drugs and Therapy Perspectives, 31 (5), pp. 167-174. DOI:http://dx.doi.org/10.1007/s40267-015-0200-6


If you have any queries about the project, please do not hesitate to contact Dr Julie Chambers on j.a.chambers@stir.ac.uk or Professor Ronan O'Carroll on reo1@stir.ac.uk