Iatrogenic diseases are defined as illnesses due to diagnostic or therapeutic 
procedures. The authors explore the possibility of recording iatrogenic diseases 
by a physician self-monitoring system. The responsible physician himself records 
his/her patients' iatrogenic complications on hospital discharge, after which 
the authors examine retrospectively all charts of the patients involved and a 
random sample of patients not included. The results show that in one year 208 of 
1618 patients were recorded as having an iatrogenic disease which was severe in 
88. 7.1% of these cases were not confirmed retrospectively (false positives). On 
the other hand, about one third of iatrogenic illnesses were not recorded (false 
negatives), though these were less severe cases only. We calculated that 17% of 
our patients had iatrogenic diseases, 22% of these were predictable. About a 
third of the patients had iatrogenic disease before hospital admission, and 
these patients had more severe, and other, iatrogenic diseases than those who 
acquired them during hospitalization. Iatrogenic complications affect other 
organ systems than non-iatrogenic acquired diseases. On average, patients with 
iatrogenic diseases were 6 years older and hospitalized 10 days longer than 
other patients. Although not all cases may be recorded, we believe that 
physician self-monitoring is preferable to other systems for recording 
iatrogenic diseases, since it may have a direct teaching effect on those who 
cause the illness.