Box 2.

Comparison of the UPC index and the SLICC

	UPC	SLICC
Developed by	Academic unit	Service general practice
Intended use	Continuity of care research	Regular continuity measurement in day-to-day general practice
Unit of measurement	Patient	Appointment
Specificity to personal doctor	Generally used so that the most frequent provider is the ‘usual’ doctor. This may be another doctor, for example, a locum or trainee	Registered personal doctor only. This is a requirement
Most-seen GP	UPC can score a doctor as usual provider when they provide a minority of the appointments, just more than other doctors. More than one doctor can be the most-seen provider	Gives a percentage of appointments that are with the personal doctor
Range of scores	A score of 0 is impossible. Consistently higher than SLICC	Can be 0–100%
Timeframe	At least two and ideally more appointments required. This can take several years in relatively healthy patients	A measure for monthly audits
Selection bias	Includes only patients with a minimum number of appointments (usually two)	Includes all appointments
Ability to take into account team continuity	No, individual provider	No, individual provider
Ability to compare patient groups	Yes, although patients with few appointments are often excluded	Yes, especially between GP lists and including infrequent attenders
Ability to obtain scores for individual patients	Yes	No
Ease of use	Simple proportion easy to calculate and interpret	Simple proportion/percentage easy to calculate and interpret

SLICC = St Leonard’s Index of Continuity of Care. UPC = usual provider of care.