Background: Ordering laboratory tests and diagnostic imaging can be part of the defensive behavior of the physician. How often does this occur in family practice in the Netherlands? Defensive behavior is defined as a clear deviation from the family physician's usual behavior and from what is considered to be good practice in order to prevent complaints or criticism by the patient or the patient's family.
Methods: Over a 1-year period, 1989-1990, 16 family physicians in 11 practices with 31,343 patients recorded all episodes of care involving an order for laboratory tests or diagnostic imaging or both (n = 8897). The physicians selected one or more reasons to order each test from a fixed list of clinical considerations. In addition, they recorded whether they acted defensively for every test order.
Results: The participating physicians reported that some degree of defensive medicine was associated with 27% of all test orders. Defensive testing varied with the clinical reasons to order a test: the wish to exclude a disease or to reassure the patient was a much stronger motive for defensive testing than the intention to confirm a diagnosis or to screen. Defensive tests generally resulted in fewer abnormal findings.
Conclusions: Defensive testing is an important phenomenon in Dutch family practice: it forms a well-defined element of practice despite the variations implicit in the different clinical reasons to order a test. Defensive testing is associated with a lower probability of finding an abnormal test result. The analysis of family physicians' clinical reasons for ordering tests becomes more meaningful when defensive testing is included.