The purpose of this study was to compare the effects of the TENS and IFC in patients with non specific chronic low back pain.

Setting Outpatient physiotherapy department in university (Cesumar)

Participants A hundred and fifty patients with non specific chronic low back pain with or without radicular pain.

Interventions The patients were randomly divided into three groups: 1) TENS; 2) IFC; e 3) Control. Ten sessions of electrotherapy for groups 1 and 2, while the patients of the Control group stayed without any treatment in the same period

Main Outcome Measures Intensity of the pain through the Visual Analogue Scale and McGill Pain Questionnaire; specific functional disability by Roland Morris Disability Questionnaire; Analgesic period (hours); and the medication consumption

Statistic Analysis All data were analyzed using Statistica version 7 and SAS version 9.1. Baseline characteristics were compared using the Shapiro-Wilks test for continuous variables and then analysis of variance for measuring independent data. The characteristics of the patients who finished the treatment were compared with those of the lost patients, using one-way ANOVA and the Kruskal-Wallis test.

Inclusion Criteria:

• Individuals who had had low back pain for less than three months

Exclusion Criteria:

• Individuals who were receiving treatment for their pain with another method at the same time, except for medicines;
• Pregnant women;
• Patients who had undergone vertebral column surgery (less than three months before the time of this study);
• Individuals with contraindications against electrotherapy, such as skin lesions, abnormal sensitivity, infectious and blood diseases, heart pacemakers or inability to answer questionnaires;
• Patients with fibromyalgia;
• Individuals with psychiatric problems;
• Individuals who refused to participate or were unwilling to follow a protocol lasting for two weeks.