Table 2.

Characteristics and parameters of the questionnaires used in this investigation in order to evaluate functional outcome and quality of life

Questionnaire	Objective	Items	Interpretation
Short form-36 (SF-36)	Quality of life (QoL)	Physical functioning Role physical Bodily pain General health perception Vitality Social functioning Role emotional Mental health	Scores 0–100 Higher Scores = Better results
Hannover functional ability score (HFAQ)	Activities of daily living (ADL)	18 items as responses to ADL	Cumulative score 0–100 Higher Score = Better result
Pain regulation questionnaire (PRQ)	Ability to compensate pain	Pain competence Pain intensity Pain depression Pain anxiety Pain avoidance Pain withdrawal Pain distraction	Scores 0–100 Higher Scores = Better results
Visual-analogue scale (VAS)	Back-related problems	19 items	Cumulative scale 0–10 Higher Scale = Better result
Posttraumatic stress screening (PTSD)	Incidence of PTSD	10 Posttraumatic stress symptoms	Score 10–70 Higher Score = Higher stress