Determining immunisation coverage rates in primary health care practices: a simple goal but a complex task.
OBJECTIVE
To explore the quality of data recording by practices and identify issues to be considered and addressed before such data can be used as a continuous measure of immunisation delivery.


METHODS
One hundred and twenty-four randomly selected general practices visited to measure immunisation coverage using the various practice management systems (PMS) in use. To capture all target children it was necessary to build two queries: one generated a list of all children aged between 6 weeks and 2 years who had been to the practice, regardless of enrollment status; the other asked dates and nature of all immunisations given. Each different PMS required a unique query to extract the necessary information.


RESULTS
Variability encountered included different types and versions of PMS and operating systems; variable degree of staff technical competence with their PMS; proportion of enrolled children ranging from nearly 0 to 100%; lack of consistency of the nature and location of data entry and coding; and unreliability of dates relating to some vaccination events.


CONCLUSIONS
To improve recording of immunisation coverage we recommend a standard early age of registration and enrollment; standard definitions of the denominator and of immunisation delay; greater uniformity of PMS; improved staff training; intrinsic data quality checks; integration of PMS with changes in the immunisation schedule; incentives and interval electronic checks to improve data quality.
Goodyear-Smith
Felicity
F
Department of General Practice and Primary Health Care, School of Population Health, Faculty of Medical and Health Sciences, The University of Auckland, New Zealand. f.goodyear-smith@auckland.ac.nz
Grant
Cameron
C
York
Deon
D
Kenealy
Tim
T
Copp
Jackie
J
Petousis-Harris
Helen
H
Turner
Nikki
N
Kerse
Ngaire
N
D006801:Humans; D007114:Immunization / Q000706:statistics & numerical data*; D016347:Medical Records Systems, Computerized / Q000458:organization & administration* / Q000706:statistics & numerical data*; D009520:New Zealand / Q000453:epidemiology; D020399:Practice Management / Q000706:statistics & numerical data*; D011320:Primary Health Care / Q000706:statistics & numerical data*