Psychometric evaluation of the Danish version of a modified Revised American Pain Society Patient Outcome Questionnaire (APS-POQ-R-D) for patients hospitalized with acute abdominal pain
Authors: Schultz Helen , Skræp Ulla , Schultz Larsen Tanja , Rekvad Lise Ewald , Littau-Larsen Jette , Schmidt Susanne Falck , Möller Sören , Qvist Niels 
Published: October 2018

Abstract

Background and aims
This paper forms part of a study evaluating the effect of patient-controlled oral analgesia for patients admitted to hospital with acute abdominal pain. Pain is a subjective experience, and a multifaceted evaluation tool concerning patient-reported outcome measures is needed to monitor, evaluate, and guide health care professionals in the quality of pain management. The Revised American Pain Society Patient Outcome Questionnaire (APS-POQ-R) is a validated multifaceted evaluation tool for measuring patient-reported pain experiences to evaluate different pain management interventions. The aim of this study was to evaluate the psychometric properties of a modified Danish version of the Revised American Pain Society Patient Outcome Questionnaire (APS-POQ-R-D) used during and after hospitalization for patients with acute abdominal pain.

Methods
The APS-POQ-R was translated into Danish and two slightly different questionnaires were formed. Questionnaire one had 39 items and the six subscales pain severity (pain), perception of care (satisfaction), pain interference with function (activity) and emotions (emotion), side effects of treatment (safety), and patient-related barriers to pain management. The questionnaire focused on time during hospital stay and was to be completed at discharge. Questionnaire two included 25 items and the five subscales pain, satisfaction, activity, emotion, and safety and focused on time at home and was to be completed daily 1 week after discharge. The questionnaires were tested on 156 patients with acute abdominal pain. Internal consistency reliability and construct validity was examined.

Results
In both questionnaires, the results of correlations and tests for internal consistency reliability showed a Cronbach’s alpha of >0.7 for the pain, activity, and emotion subscales, but the value was ≥0.69 for the satisfaction subscale. In questionnaire one, Cronbach’s alpha was ≤0.64 for the safety subscale, but this was 0.73 when the item “itching” was deleted. In questionnaire two, Cronbach’s alpha was ≤0.51 for the safety subscale. For the patient-barrier subscale in questionnaire one, Cronbach’s alpha was ≤0.62 for any combination of the items in the subscale. The results of the construct validity and factor analysis showed a five-factor structure in questionnaire one and a three-factor structure in questionnaire two. In questionnaire one, items from the pain, activity, emotion, and safety subscales, except for the items “least pain” and “itching,” loaded on factor one. In questionnaire two, all items from the pain, activity, and emotion subscales loaded on factor one.

Conclusions
The modified APS-POQ-R-D demonstrated adequate psychometric properties for the five subscales pain severity (pain), perception of care (satisfaction), pain interference with function (activity) and emotions (emotion), side effects of treatment (safety), but not for the patient-barrier subscale for patients hospitalized with acute abdominal pain. Consequently, the APS-POQ-R-D may be used without the patient-barrier subscale.

Implications
The clinical implications of this study may help clinicians with investigating how acute patients manage pain during and after hospital admission.