<p>Integrating laboratory information into prescribing tasks may improve medication safety. This thesis addresses several methodological issues in the progress of two studies: a systematic review of randomized trials addressing the impact of drug-lab safety alerts on adverse drug events and changes in prescribing or lab monitoring and a randomized trial using an electronic survey to compare prescribing decisions in complex clinical scenarios including integrated lab data with those in which the lab data were available on request. The systematic review found 32 studies; 10 addressed multiple drug-lab combinations, and 22 addressed single drug-lab combinations, including 14 targeting anticoagulation. We report a benefit of anticoagulation-related alerts (OR of an adverse event (bleeding or thrombosis) 0.88 (95% CI 0.78-1.00) and improved prescribing in multi-drug studies (OR 2.22, 95% CI 1.19-4.17), but substantial study heterogeneity precluded combining studies of other drugs. Methodological issues addressed in the RCT include medication selection, scenario design, recruitment, and assessment of the representativeness of the sample. We selected medications for study scenarios that are commonly prescribed by Canadian primary care physicians, and are associated with clinically important harm that may be preventable through laboratory monitoring. Data sources included IMS Brogan data on prescribing patterns and the Discharge Abstracts Database (DAD) and the National Ambulatory Care Reporting System (NACRS) from 2006-2007 to 2008-2009. Our study had 148 completed surveys. The study sample differed from the population of Ontario family physicians by gender, and use of electronic medical records. We found no difference in prescribing decisions (OR 1.21, 95% CI 0.84-1.75) between the study groups and no predictors of improved prescribing decisions. The lack of demonstrated impact of integrating lab data into clinical decision-making may be related to the study being underpowered, to a true lack of clinical benefit, or to a lack of discriminatory power in the scenarios.</p> / Master of Science (MSc)

The overall aim of this thesis was to explore aspects of the subjective views and experiences of doctors as prescribers, focusing on responsibility for and factors of importance in achieving appropriate prescribing. To provide insights into the prescriber’s perspective the study designs were qualitative. In the first studies secondary care doctors’ perceptions of appropriate prescribing and influences in prescribing were investigated in interviews. The doctors perceived that appropriate prescribing needed continuous revision. From the perspective of the prescribers the definition of prescribing could be rephrased as: “the outcome of the recurring processes of decision making that maximises net individual health gains within society’s available resources”. Among the influences in prescribing were guidelines, colleagues and therapeutic traditions. In the subsequent studies the experiences of exchanging information regarding a patient’s drugs in an electronic patient medical record (e-PMR) shared between primary and secondary care and views of responsibility was explored, using focus groups with both primary and secondary care doctors. Considering the gap between health care levels, doctors’ views of responsibility in prescribing and exchange of information are of concern. The doctors expressed how they assume information to be in the e-PMR and active information transfer has decreased. On the other hand, they experienced an information overload in the e-PMR system. There is a need for improved and structured communication between health-care givers. Taking responsibility to review all the patient’s medications was perceived as important, but described as still not done. Lack of responsibility taken was often due to acts of omission, i.e. that doctors did not make needed changes to the list of medications due to different barriers. The barriers rested both with individual doctors and the system, but to ensure solutions that are realisable in practise, perspectives of the doctors need to be taken into consideration when overcoming those barriers.