What is the optimal outcome measure for whiplash?

Whiplash associated disorder (WAD) is extensively treated and investigated within the physiotherapy profession. Despite significant guidelines and recommendation, the patient reported outcomes (PROs) for measurement of individual status and progress are predominantly advocated from a subjective non-evidence based protocol. This study investigated the performance of seven PROs obtained from published and grey literature that were recommended for WAD: Neck Disability Index (NDI), Whiplash Disability Questionnaire (WDQ), Functional Rating Index (FRI), Numeric Rating Scale (NRS) 11-point, Patient Specific Index (PSI), Spine Functional Index (SFI) and Global Assessment (GABAL) composite scale. A total of 30 patients, age 37 ± 14, 77% female, from a convenience sample in 8 primary care centres were measured at baseline, 1, 3 and 6 months to produce 120 measurements with 744 of 840 individual responses (11% missing responses). All PRO scores were on a 100% scale. Overall PRO performance was compared using the Measurement of Outcomes Measures (MOM) quantitative scale (25 × 3-point items = 100%) and the ‘Bot’ quantitative scale (12 dichotomous items). The best performed tools were the PSI (96%, 12/12) however it cannot compare between patients, and the Global compositescale (92%, 12/12) which requires computer software. The optimal PRO was the SFI (90%, 12/12) then the NRS (86%, 12/12), FRI (80%, 10/12), NDI (66%, 8/12) and WDQ (52%, 5/12). The most commonly used and advocated PRO, the NDI, had poor distribution and within-tool item ranking. The best performed WAD measurements were the PSI and GABAL composite-scales, whilst the optimal clinical PRO was the SFI. Measurement of patient status and subsequent comparison to produce evidence that justifies current or further intervention is now obligatory in most physiotherapy and primary care settings. However, the role of advocacy for the optimal PRO to achieve these measures in a clinically practical and methodological sound manner is often flawed by the use of personal opinion and subjective attitudes rather than the scientific quantitative data to support such recommendations. Examples of this include those advocated by physiotherapy teaching institutions, the APA and most State government insurance group web sites. A re-evaluation of why a PRO is advocated is required and a need to quantify the choice using a-priori protocol