Quality of Life Research

, Volume 21, Issue 3, pp 441–451 | Cite as

Applying mixed methods to pretest the Pressure Ulcer Quality of Life (PU-QOL) instrument

  • C. Gorecki
  • D. L. Lamping
  • J. Nixon
  • J. M. Brown
  • S. Cano
Article

Abstract

Purpose

Pretesting is key in the development of patient-reported outcome (PRO) instruments. We describe a mixed-methods approach based on interviews and Rasch measurement methods in the pretesting of the Pressure Ulcer Quality of Life (PU-QOL) instrument.

Methods

We used cognitive interviews to pretest the PU-QOL in 35 patients with pressure ulcers with the view to identifying problematic items, followed by Rasch analysis to examine response options, appropriateness of the item series and biases due to question ordering (item fit). We then compared findings in an interactive and iterative process to identify potential strengths and weaknesses of PU-QOL items, and guide decision-making about further revisions to items and design/layout.

Results

Although cognitive interviews largely supported items, they highlighted problems with layout, response options and comprehension. Findings from the Rasch analysis identified problems with response options through reversed thresholds.

Conclusions

The use of a mixed-methods approach in pretesting the PU-QOL instrument proved beneficial for identifying problems with scale layout, response options and framing/wording of items. Rasch measurement methods are a useful addition to standard qualitative pretesting for evaluating strengths and weaknesses of early stage PRO instruments.

Keywords

Pressure ulcer Health-related quality of life Patient-reported outcome Mixed methods 

Abbreviations

PU

Pressure ulcer

HRQL

Health-related quality of life

PRO

Patient-reported outcome

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • C. Gorecki
    • 1
  • D. L. Lamping
    • 2
  • J. Nixon
    • 1
  • J. M. Brown
    • 1
  • S. Cano
    • 3
  1. 1.Clinical Trials Research Unit (CTRU)University of LeedsLeedsUK
  2. 2.Department of Health Services Research and PolicyLondon School of Hygiene & Tropical MedicineLondonUK
  3. 3.Clinical Neurology Research GroupPeninsula College of Medicine and DentistryPlymouthUK

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