The interplay of acceptance and effectiveness in intervention studies: the example of the empCARE training to reduce burnout and distress symptoms in health care providers.

Objective: Although almost every study evaluating psychological interventions includes the two components of acceptability and effectivity, their relationship is rarely examined. The current study closes this gap by performing secondary analyses of the intervention program 'empCARE'. The goal was to analyze the relationship between these two evaluation components.

Design: The sample consists of 309 nurses (intervention group  = 172; control group  = 137). Data were collected before the training and longitudinally three times after the training.

Main Outcome Measures: Psychological distress was assessed using the Symptom Checklist (SCL-90-R), and the Copenhagen Burnout Inventory. Personality traits were assessed using the HEXACO-60 and the Toronto Empathy Questionnaire. Acceptability was assessed using statements concerning participants' subjective evaluation of the training.

Results: The results show that the intervention program was effective. Acceptability, measured only in the intervention group, was quite high. However, no connection was found between effectivity and acceptability. On the contrary, the results show that acceptability assessments depend more on personality factors than on intervention success.

Conclusions: Researchers should examine the relationship between acceptability and effectivity in their data. It does not seem appropriate to rely on acceptability measurements as the sole evaluation criterion capturing the success of an intervention.