Persistent physical symptoms (PSS) are consistently prevalent among primary care patients. PSS can negatively affect quality of life, healthcare costs, and work participation. To examine predictors of treatment outcome in patients with who received treatment by a work-focused communication tool known as the Individual Challenge Inventory Tool (ICIT) delivered by the patient's general practitioner. In a previous study we found substantially improved outcomes and reduced sick leave for patients treated by the work-focused communication tool ICIT compared to a control group. This study is based on the findings of our previous cluster randomised controlled trial. Regression analyses of the intervention group were used to identify predictors (all measured at baseline) of improvements in Patient Global Impression of Change (PGIC) and sick leave after 11 weeks follow up. Living alone predicted improvement in the adjusted model (OR =4·03, 95% CI: 1·33-12·25, P=0·014). Receiving long term benefits predicted improved PGIC in both the unadjusted (OR =2·30, 95% CI: 1·21-4·39, P=0·011) and adjusted models (OR =2·46, 95% CI: 1·04-5·83, P=0·040). In addition, living alone predicted reduced sick leave in the adjusted model (OR =3·23, 95% CI: 1·11-9·42, P=0·032. In general, there were few factors to predict the outcome of the work-focused communication tool ICIT. We therefore suggest that this work-focused communication tool ICIT is applicable to most patients with PPS. GPs may consider using the ICIT for all primary care patients who exhibit ineffective coping strategies in their daily lives and work, especially those who live alone.