Development of a Computerised Adaptive Testing and Equalisation Approaches to Assess Sleep and Quality of Life in Chronic Pain

Background

Computerised adaptive testing (CAT) and equalisation are statistical approaches that mitigate questionnaire response burden by selecting individually tailored items according to previous response patterns; they facilitate comparing results across distinct instruments by providing conversion functions between their scores, respectively. However, they have seldom been specifically applied to the general chronic pain population. This study aimed at developing CAT and equalisation approaches for widely used sleep quality and quality of life (QoL) assessment instruments.

Methods

This prospective cross-sectional study included adult participants with chronic pain treated at specialised tertiary-care clinics. Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI) were used for investigating sleep quality construct; and the 12-Item Short Form Health Survey, WHOQoL-BREF and 5 dimensions 3 levels EuroQol for QoL. CATs were developed for these two constructs based on graded model item response theory. Equalisation utilised equipercentile methodology.

Results

Three-hundred participants (54.4 ± 13.8 years-old, female = 54.7%) with different chronic pain diagnoses, 77.3% of whom were neuropathic, were enrolled. CATs were developed for both constructs, with adequate model fit. A 5000-response simulation demonstrated average reductions of 80.6% and 76.8% in items required to be answered for evaluating sleep quality and QoL, respectively, when compared to the total original questionnaire items. Equalisation functions were described for score conversions between WHOQoL-BREF and 12-Item Short-Form Health Survey, and between PSQI and ISI.

Conclusions

This initial study demonstrated the feasibility of CATs for assessing sleep quality and QoL in chronic pain populations; and provided equalisation functions between instruments widely used for these purposes. Future replication and validation are necessary to establish the generalisability of these findings.

Significance

The high response burden inherent to the use of multiple validated instruments to assess quality of life (QoL) and of sleep undermines their systematic application in the assessment of chronic pain, both in daily practice and research settings. To address this gap, this initial study demonstrated the feasibility of employing computerised adaptive testing for this purpose within a population with diverse chronic pain conditions; and provided equalisation functions that allow for crosstalk between widely used QoL and sleep assessment tools.