Summary

Objectives: To improve the recording of diagnostic discharge data, pediatricians encoded diagnostic information as part of discharge letter writing supported by a pediatric list of ICD-9-CM-based codes. We evaluated the effect of this new policy on level of detail and number of recorded diagnoses. Methods: We compared proportions of specific principal diagnoses and numbers of secondary diagnoses of the four years before with the eight years after introduction. Results: Immediately after introduction, half of the diagnoses for which both generic and specific codes existed was coded specific. In later years this proportion remained stable at 0.35 (p <0.05). Diagnoses that fall under the pediatrician’s own subspecialty had more often a specific code than diagnoses that do not. The mean number of secondary diagnoses per admission increased from 0.7 before introduction to 1.4 in the third year after introduction (p <0.05) but gradually fell back to 0.7. This increase and decrease was mainly due to diagnoses that did not fall under the pediatrician’s own subspecialty. The extra codes in individual discharge summaries had added informational value. Conclusions: Discharge letter-linked encoding by pediatricians supported by a pediatric list of diseases leads initially to increased detail and number of diagnoses with added informational value. When attention diminishes, especially the level of detail and number of secondary diagnoses that do not fall under one’s own subspecialty decrease. The level of detail of principal diagnoses remains stable because of the advantage for pediatricians of having specific diagnostic codes falling under their own subspecialty.