background In routine outcome monitoring (rom) generic instruments are often used to measure outcomes. This could hamper the clinical use of these instruments and lead to a possible underestimation of treatment outcomes.
aim To examine whether there are differences in the degree of progress between outcomes of disorder specific instruments measuring anxiety symptoms and the Symptomatic Distress subscale of the Outcome Questionnaire-45 (oq-45-sd).
method Data from 604 patients with an anxiety disorder were analyzed. The mean change scores, percentages of reliable change and effect sizes on the oq-45-sd were compared to the outcomes of seven commonly used instruments that specifically measure the symptoms of anxiety disorders.
results The effect sizes on the oq-45-sd and the disorder specific instruments were 0.80 or higher. The correlation between the change scores was moderate, as was the correspondence between the degree to which patients improved reliably. In one third to half of the cases changes on the oq-45-sd and on the disorder specific instruments were not in agreement.
conclusion The treatment outcomes of the oq-45-sd are approximately as positive as those of the disorder specific instruments. However, discrepancies existed in the extent to which patients had improved. In accordance with the advice of the International Consortium for Health Outcomes Measurement, the use of both kinds of instruments is advised when evaluating the progress of the treatment.