ABSTRACT
OBJECTIVES: To investigate for individual patients who have been using NSAIDs regularly, whether paracetamol is as effective as non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of pain and disability related to osteoarthritis of the hip or knee. METHODS: A series of n of 1 trials were conducted in general practices in Amsterdam and the surrounding area. Each patient was his or her own control and received five pairs of treatments comprising two weeks of an NSAID and two weeks of paracetamol. For each pair, the order of treatments was randomised. Outcome measures were severity of individual main complaints, intensity of pain, satisfaction with drugs, function test, and side effects. RESULTS: Thirteen patients were selected. Six patients did not complete the study. For five patients completing the study little or no difference was found between NSAIDs and paracetamol, for one patient the results favoured the NSAID, and for one patient there was no association between outcome and type of drug. It was recommended that six patients changed to paracetamol; the others continued with NSAIDs. Three months after the end of the study, four of the six patients for whom paracetamol had been recommended were taking NSAIDs for practical reasons or perceived lack of efficacy. CONCLUSION: The results of the n of 1 trials varied across patients. n of 1 trials can be used to investigate which treatment is best for any specific person, thus avoiding unnecessary prolonged treatment with NSAIDs. However, practical reasons may cause patients to switch from NSAIDs to paracetamol or not.
Subject(s)
Acetaminophen/therapeutic use , Analgesics, Non-Narcotic/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Osteoarthritis, Hip/drug therapy , Osteoarthritis, Knee/drug therapy , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Treatment OutcomeABSTRACT
Literature concerning the value of diagnostic tests is poorly indexed in electronic bibliographical databases. An extensive, sensitive and specific search strategy for evaluation of a diagnostic test in Medline is a combination of key words or text words concerning the diagnostic test with: 'sensitivity and specificity' (exploded), 'mass screening' (exploded), 'reference values', 'false positive reactions', 'false negative reactions', 'specificit$.tw', 'screening.tw', 'false positive$.tw', 'false negative$.tw', 'accuracy.tw', 'predictive value$.tw', 'reference value$.tw', 'roc$.tw' or 'likelihood ratio$.tw'. Inclusion and exclusion criteria select publications which meet certain minimum requirements, such as the presence of an accepted reference standard, a clear definition of 'diseased', and the presence of a suitable outcome measure. The methodological assessment list should contain a number of validity criteria as well as a number of criteria by which to measure the extent to which the study results can be generalised. Important assessment criteria that may affect the diagnostic value of the test are: study design, blinding, use of different reference standards, the absence of details about the diagnostic criteria for the diagnostic test and insufficient information about the study population.
