Patients' beliefs about their lack of pain control in primary fibromyalgia syndrome.

This study had two aims, first, to determine the expectancies of control over pain experience ('pain locus of control') of patients with primary fibromyalgia syndrome (PFS) and to compare them with other chronic rheumatic diseases. Second, to analyse the relationships between health status and locus of control. We applied the Multidimensional Health Locus of Control-Pain and the Arthritis Impact Measurement Scales (AIMS), by interviewing 137 out patients (32 PFS, 32 RA, 20 SLE, 22 AS and 31 OA). Data were analysed by ANOVA and partial correlation tests. PFS patients believed that their symptoms depended on uncontrollable events and that they could not influence their disease by themselves. PFS patients were the most disabled on the 'Affect' (P < or = 0.001) and 'Symptom' factors (P < or = 0.01). In the PFS group, patients who showed a 'Fate' locus of control orientation reported more disability on 'Affect' and 'Social Interaction' AIMS factors.