Paper versus electronic rating scales for pain assessment: a prospective, randomised, cross-over validation study with 200 chronic pain patients

Research design/methodology

TYPE: Prospective design with participants randomized to one of two groups: (1) paper pain questionnaire prior to the physician’s appointment and then a PDA-based questionnaire afterwards, or (2) vice versa.

VALIDITY: There is potential bias with one of the researchers being a Pfizer employee - however, this was not a pharmacologic study.  Limitations include single site design and exclusion of patients deemed unlikely to have the ability to complete the PDA questionnaire.  Detailed description of the exclusion criteria is needed.  The study's strengths are the recruitment of community-based chronic pain patients in a clinical setting and the vast majority of the patients approached was willing to participate and completed the study.  Patients served as their own controls in measurements of the time taken to complete questionnaire. 

ENVIRONMENT: Conducted at a private physician’s pain clinic in Germany

Research question

To determine whether electronically acquired (via PDA) patient-entered Visual Analog Scales (VAS) for pain are well correlated with those entered by hand onto paper.

The main outcome measure was the patient’s average pain over the preceding 4 weeks. Other measured outcomes were present pain severity, worst pain over the preceding 4 weeks, and the painDETECT score.

Patient/Problem/Population definition

PATIENT: pain patients

PROBLEM: The use of PDA-based pain questionnaires has not been validated.

POPULATION: Male and female patients aged 17 to 94 years attending a pain clinic with any chronic pain and the ability, in the investigator’s opinion, to use a PDA.

TYPE: clinical research, health services research

Intervention

Using a PDA to record pain questionnaires

Comparison

PDA tool versus pen-and-paper pain questionnaire

Outcome

No statistically significant difference was observed between PDA questionnaire results and paper-based questionnaire results for measurements of average pain over the preceding 4 weeks, present pain and the painDETECT score.  There was a statistical difference for worst pain over the preceding 4 weeks: patients consistently recorded a lower score on the PDA as compared to paper.

The effects were precise because of the recruitment of a sufficient sample size (according to power calculations) and the relatively narrow confidence intervals in the results.

Application of results to patient care

This study concludes that results from PDA-based questionnaires are very similar to those generated on paper. These electronic questionnaires may be successfully used in a pain medicine practice. 

Further areas for research  

Further studies with less technologically adept patients are warranted.