PMID- 17057565
OWN - NLM
STAT- MEDLINE
DCOM- 20061213
LR  - 20220409
IS  - 0749-8047 (Print)
IS  - 0749-8047 (Linking)
VI  - 22
IP  - 9
DP  - 2006 Nov-Dec
TI  - Sensitivity to change and internal consistency of the Northwick Park Neck Pain 
      Questionnaire and derivation of a minimal clinically important difference.
PG  - 820-6
AB  - OBJECTIVES: To estimate the sensitivity to change and internal consistency of the 
      Northwick Park Neck Pain Questionnaire (NPQ) and derive its minimal clinically 
      important difference (MCID). METHODS: Data on 311 participants in a randomized 
      controlled trial of physical therapy for neck pain were analyzed, between 
      baseline and 6-month follow-up. Cronbach alpha was used to estimate internal 
      consistency. Three methods of evaluating the NPQ's sensitivity to change were 
      used; Cohen's effect size, standardized response mean, and Guyatt's 
      responsiveness statistic. The smallest change on the NPQ that can be construed as 
      clinically important (the MCID) was obtained by (1) comparing values derived from 
      different methods that account for the measurement error of the questionnaire 
      with improvements in other neck pain-specific measures, and then (2) examining 
      the impact of the addition of an independent measure ("anchor") relating to 
      participants' subjective rating of improvement. RESULTS: Cronbach alpha was 0.79 
      for the whole scale. Using all participants, Cohen's d was 0.78, standardized 
      response mean was 0.71, and Guyatt's responsiveness statistic was 0.93. Using 
      only participants who stated they had improved, the estimates were 1.35, 1.27, 
      1.45, respectively. The MCID for the NPQ was determined as a 25% reduction in 
      score from baseline together with a patient's global rating of their neck pain of 
      at least "better." CONCLUSIONS: These results show high internal consistency and 
      sensitivity to change for the NPQ, and provide an MCID that allows participants 
      with varying levels of severity to demonstrate improvement.
FAU - Sim, Julius
AU  - Sim J
AD  - Primary Care Musculoskeletal Research Centre, Keele University, Staffordshire ST5 
      5BG, UK. j.sim@keele.ac.uk
FAU - Jordan, Kelvin
AU  - Jordan K
FAU - Lewis, Martyn
AU  - Lewis M
FAU - Hill, Jonathan
AU  - Hill J
FAU - Hay, Elaine M
AU  - Hay EM
FAU - Dziedzic, Krysia
AU  - Dziedzic K
LA  - eng
PT  - Journal Article
PT  - Randomized Controlled Trial
PL  - United States
TA  - Clin J Pain
JT  - The Clinical journal of pain
JID - 8507389
SB  - IM
MH  - Adult
MH  - Aged
MH  - Aged, 80 and over
MH  - Female
MH  - Humans
MH  - Male
MH  - Middle Aged
MH  - Neck Pain/*diagnosis/epidemiology/*therapy
MH  - Outcome Assessment, Health Care/*methods
MH  - Pain Measurement/*methods
MH  - Prognosis
MH  - Reproducibility of Results
MH  - Sensitivity and Specificity
MH  - *Surveys and Questionnaires
MH  - Treatment Outcome
MH  - United Kingdom/epidemiology
EDAT- 2006/10/24 09:00
MHDA- 2006/12/14 09:00
CRDT- 2006/10/24 09:00
PHST- 2006/10/24 09:00 [pubmed]
PHST- 2006/12/14 09:00 [medline]
PHST- 2006/10/24 09:00 [entrez]
AID - 00002508-200611000-00011 [pii]
AID - 10.1097/01.ajp.0000210937.58439.39 [doi]
PST - ppublish
SO  - Clin J Pain. 2006 Nov-Dec;22(9):820-6. doi: 10.1097/01.ajp.0000210937.58439.39.