Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Randomized Controlled Trial
. 2017 Jan;18(1):54-65.
doi: 10.1016/j.jpain.2016.10.002. Epub 2016 Oct 17.

Identifying Treatment Effect Modifiers in the STarT Back Trial: A Secondary Analysis

Jason M Beneciuk  1 , Jonathan C Hill  2 , Paul Campbell  2 , Ebenezer Afolabi  2 , Steven Z George  3 , Kate M Dunn  2 , Nadine E Foster  2
Affiliations
Randomized Controlled Trial

Identifying Treatment Effect Modifiers in the STarT Back Trial: A Secondary Analysis

Jason M Beneciuk et al. J Pain. 2017 Jan.

Abstract

Identification of patient characteristics influencing treatment outcomes is a top low back pain (LBP) research priority. Results from the STarT Back trial support the effectiveness of prognostic stratified care for LBP compared with current best care, however, patient characteristics associated with treatment response have not yet been explored. The purpose of this secondary analysis was to identify treatment effect modifiers within the STarT Back trial at 4-month follow-up (n = 688). Treatment response was dichotomized using back-specific physical disability measured using the Roland-Morris Disability Questionnaire (≥7). Candidate modifiers were identified using previous literature and evaluated using logistic regression with statistical interaction terms to provide preliminary evidence of treatment effect modification. Socioeconomic status (SES) was identified as an effect modifier for disability outcomes (odds ratio [OR] = 1.71, P = .028). High SES patients receiving prognostic stratified care were 2.5 times less likely to have a poor outcome compared with low SES patients receiving best current care (OR = .40, P = .006). Education level (OR = 1.33, P = .109) and number of pain medications (OR = .64, P = .140) met our criteria for effect modification with weaker evidence (.20 > P ≥ .05). These findings provide preliminary evidence for SES, education, and number of pain medications as treatment effect modifiers of prognostic stratified care delivered in the STarT Back Trial.

Perspective: This analysis provides preliminary exploratory findings about the characteristics of patients who might least likely benefit from targeted treatment using prognostic stratified care for LBP.

Keywords: Low back pain; socioeconomic status; stratified care; subgrouping; treatment effect modification.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Poor treatment response by socioeconomic status
Figure 2
Figure 2
Decomposed treatment response by socioeconomic status interactions. Reference: Control /Low SES SES = socioeconomic status; OR = odds ratio; CI = confidence interval.
Figure 3
Figure 3
Poor treatment response by level of education.
Figure 4
Figure 4
Poor treatment response by number of pain medications.
See this image and copyright information in PMC

References

    1. Adler NE, Newman K. Socioeconomic disparities in health: pathways and policies. Health affairs (Project Hope) 2002;21:60–76. - PubMed
    1. American Psychological Association. Report of the APA Task Force on Socioeconomic Status. Washington, DC: 2007. Availiable at: http://www.apa.org/pi/ses/resources/publications/index.aspx.
    1. Bartley EJ, Fillingim RB. Sex differences in pain: a brief review of clinical and experimental findings. British journal of anaesthesia. 2013;111:52–58. - PMC - PubMed
    1. Bialosky JE, Bishop MD, Cleland JA. Individual expectation: an overlooked, but pertinent, factor in the treatment of individuals experiencing musculoskeletal pain. Physical therapy. 2010;90:1345–1355. - PMC - PubMed
    1. Brookes ST, Whitely E, Egger M, Smith GD, Mulheran PA, Peters TJ. Subgroup analyses in randomized trials: risks of subgroup-specific analyses; power and sample size for the interaction test. Journal of clinical epidemiology. 2004;57:229–236. - PubMed

Publication types