Computer simulation models are used increasingly to support public health research and policy, but questions about their quality persist. The purpose of this article is to review the principles and methods for validation of population-based disease simulation models.
The concept of participation is recognized as an important rehabilitation outcome and instruments have been developed to measure participation using the International Classification of Functioning, Disability and Health (ICF). To date, few studies have examined the content of these instruments to determine how participation has been operationalized. The purpose of this study was to compare the content of participation instruments using the ICF classification.
Purpose: We compared health-related quality of life (HRQL), symptoms, and convenience of care (COC) in patients with stage II/III carcinoma of the colon who received either oral uracil/ftorafur (UFT) plus leucovorin (LV) or standard intravenous (IV) fluorouracil (FU) plus LV as adjuvant chemotherapy. Patients and Methods: We measured HRQL with the Functional Assessment of Cancer Therapy–Colorectal (FACT-C) questionnaire, Short Form-36 Vitality Scale (SF-36), and a Quality of Life Rating Scale (QLRS) at baseline, once during chemotherapy, and at 1 year. We used the Symptom Distress Scale (SDS) and treatment-specific Symptom Checklist (SCL) to assess symptoms and a modified Burden of Care form to assess COC at baseline, on day 1 of each treatment cycle, and at 1 year. Repeated measures analyses controlling for demographic variables and baseline scores were used for statistical comparisons. Results: The study accrued 1,608 patients, 803 to the FU arm and 805 to the UFT arm. There were no differences between the arms in overall FACT-C scores, FACT-C scores within the subscales of colon-specific, physical, emotional, social, and functional health, or QLRS scores. Patients taking UFT reported substantially higher COC. Statistically significant but small differences were observed for SF-36, favoring FU, and for SDS and SCL, both favoring UFT. Conclusion: Patients perceive adjuvant treatment with UFT + LV as more convenient than standard IV treatment with FU + LV. Both regimens are well tolerated and do not differ in their impact on HRQL.
The POpulation HEalth Model (POHEM) is a health microsimulation model that was developed at Statistics Canada in the early 1990s. POHEM draws together rich multivariate data from a wide range of sources to simulate the lifecycle of the Canadian population, specifically focusing on aspects of health. The model dynamically simulates individuals’ disease states, risk factors, and health determinants, in order to describe and project health outcomes, including disease incidence, prevalence, life expectancy, health-adjusted life expectancy, quality of life, and healthcare costs. Additionally, POHEM was conceptualized and built with the ability to assess the impact of policy and program interventions, not limited to those taking place in the healthcare system, on the health status of Canadians. Internationally, POHEM and other microsimulation models have been used to inform clinical guidelines and health policies in relation to complex health and health system problems. This paper provides a high-level overview of the rationale, methodology, and applications of POHEM. Applications of POHEM to cardiovascular disease, physical activity, cancer, osteoarthritis, and neurological diseases are highlighted.