Introduction

RSOC is one way of measuring continuity of care. Mustard et al. (1996) created a measure of regular source of care for children by enumerating all ambulatory medical services provided to children from birth to 60 months of age. Ambulatory care was defined to include office visits and visits to outpatient or emergency departments in a hospital setting. Diagnostic laboratory tests and imaging examinations were excluded from this definition.

Methodology

For each child, ambulatory medical services were counted for individual physicians providing care for the child, and this count was expressed as a proportion of all ambulatory visits. Individual physicians were identified by the use of unique numeric identifiers assigned to physicians by the provincial health insurance agency. The physician providing the greatest proportion of care in a specified time period was defined as the regular source of care.

Using this method, a number of adjustments were made to reflect the organization and delivery of medical care in this setting.


1. For physicians in a group practice, they enumerated visits at the level of the practice, rather than the individual physician.
   
2. Where a child was seen by a physician in referral or consultation, they attributed the visit back to the primary care physician who originated the referral.
   
3. In the case of academic physicians who may provide care under alternate billing numbers, they consolidated all services provided by that physician.

This method was used to determine the regular source of care for two consecutive time periods: 0 through 24 months from birth and 25 through 60 months. The partitioning of each child's experience into two time periods was performed to reflect the different patterns of primary care in infancy and early childhood expected to have impacts on the measurement of continuity of care.