Adjusted Clinical Groups use as a measure of the referrals efficiency from primary care to specialized in Spain

To determine the referral rate (RR) per centre, its main causes and the adjusted efficiency indexes, through the retrospective implementation of the Adjusted Clinical Groups (ACG) in a Spanish primary care setting.

Design descriptive-retrospective study. Attended patients by five primary care teams (PCT) during the year 2004 were included. General parameters, age, gender, dependent (visits and episodes), and comorbidity of each patient relative to each ACG are used as measures. The RR was defined as the quotient between the number of referrals and the visits made. Efficiency Index (EI) was established dividing the observed by the expected referrals obtained by indirect standardization. Statistical significance P<0.05.

Studied patients 81,335 (use: 76.9%), 5.0+/-3.6 episodes and 7.9+/-7.8 visits/patient/year. Percentage of visits with a referral, adjusted for morbidity burden, was 7.5% (CI: 7.3-7.7); age: 48.3+/-22.7 years (women: 55.9%), P=0.000. The average of referrals was of 59.6 per 100 attended patients/year (P=0.000). Visits and episodes explain 34.1-68.1%, respectively (P=0.000), the explanatory power of the classification's variability was of 23.6% (P=0.0001). EI per centre were: 0.95 (CI: 0.82-1.08); 0.78 (CI: 0.63-0.93); 0.88 (CI: 0.73-1.03); 1.15 (CI: 1.03-1.27) and 1.08 (CI: 0.95-1.21), P=0.034 (family practice); and 0.83 (CI: 0.70-0.96); 0.83 (CI: 0.68-0.98); 0.84 (CI: 0.70-0.98); 1.24 (CI: 1.12-1.36) and 1.16 (CI: 1.03-1.29), P=0.041 (paediatrics), respectively.

Adjusted morbidity by ACG explains an important part of the referrals variability. The study results must be interpreted cautiously even after adjustment by age, gender and morbidity. Should the results be confirmed, it would allow an improvement in the measurement of referrals for clinical management in the PCT.