Construct and discriminant validity of STarT Back Screening Tool - Brazilian version

Area of Science:

• Low back pain management
• Clinical assessment tools
• Psychosocial factors in physical disability

Background:

• The STarT Back Screening Tool (SBST) aids in stratifying low back pain patients by disability risk for targeted primary care.
• This study evaluates the Brazilian version of the SBST (SBST-Brazil) for its psychometric properties.

Purpose of the Study:

• To assess the construct validity of the SBST-Brazil.
• To determine the discriminative validity of the SBST-Brazil.

Main Methods:

• 151 low back pain patients were assessed at baseline.
• Construct validity was measured using Spearman's rank-order correlation against the Oswestry Disability Index (ODI) and Roland Morris Disability Questionnaire (RMDQ).
• Discriminative validity was assessed using Area Under the Curve (AUC) from Receiver Operating Curves (ROC) against the Fear-Avoidance Beliefs Questionnaire (FABQ).

Main Results:

• SBST-Brazil total and psychosocial scores showed moderate to good correlations with ODI (r=0.61, r=0.56) and RMDQ (r=0.70, r=0.64).
• Correlations with FABQ subscales were weak to moderate (FABQ-PA: r=0.28, r=0.34; FABQ-W: r=0.18, r=0.20).
• Discriminant validity (AUC) ranged from 0.66 (kinesiophobia) to 0.88 (disability).

Conclusions:

• The SBST-Brazil demonstrates moderate to good construct validity with disability measures.
• The tool shows weak correlation with fear-avoidance beliefs but good discriminative ability for patients with disability and fear-avoidance.
• SBST-Brazil is a valid tool for discriminating low back pain patient subgroups in Brazil.