Clustering of patients with chronic low back pain in terms of physical and psychological factors: A cross-sectional study based on the STarT Back Screening Tool

Article type: Research Article

Authors: Yadollahpour, Nava | Zahednejad, Shahla^* | Yazdi, Mohammad Jafar Shaterzadeh | Esfandiarpour, Fatemeh

Affiliations: Musculoskeletal Rehabilitation Research Center, School of Rehabilitation Sciences, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran

Correspondence: [*] Corresponding author: Shahla Zahednejad, Musculoskeletal Rehabilitation Research Center, School of Rehabilitation Sciences, Ahvaz Jundishapour University of Medical Sciences, Ahvaz, Iran. Tel.: +986113743101-3; Fax: +986113743506; E-mail: dr.shzahed@gmail.com.

Abstract: BACKGROUND: The STarT Back Screening Tool (SBT) is a multidimensional questionnaire consisting of physical and psychological factors which categorizes the patients in the low, medium or high risk subgroups. OBJECTIVE: To investigate the relationship between SBT-based subgrouping and clustering of patients with LBP using uni-dimensional psychological, clinical and physical examination measures. METHODS: One hundred and fifty-seven patients with chronic LBP completed the SBT and uni-dimensional psychological, disability and pain questionnaires. Physical impairments were evaluated through the Physical Impairment Index (PII). Hierarchical and K-means methods were used for cluster analysis. Between-clusters differences and the association between the clusters and SBT-based subgrouping were investigated. RESULTS: Three clusters were identified. The derived clusters were labeled severe, moderate and mild physical-psychological-distress clusters, because pain intensity, disability, psychological and physical factors were relatively high, moderate or low, respectively. Most of the patients in moderate and mild physical-psychological distress clusters were categorized as medium risk based on SBT. The mean difference for the PII was higher than that of psychological factors between moderate and mild physical-psychological-distress clusters. CONCLUSIONS: Patients in low and high risk subgroups of SBT were sufficiently differentiated, but patients in a medium risk subgroup had a different profile based on PII. Including additional physical factors in the SBT may be required to better differentiate among patients.

Keywords: Physical factors, psychological factors, low back pain, clustering, STarT Back Screening Tool

DOI: 10.3233/BMR-181484

Journal: Journal of Back and Musculoskeletal Rehabilitation, vol. 33, no. 4, pp. 581-587, 2020