Effects of vitamin D on patients with fibromyalgia syndrome: a randomized placebo-controlled trial.

The role of calcifediol in the perception of chronic pain is a widely discussed subject. Low serum levels of calcifediol are especially common in patients with severe pain and fibromyalgia syndrome (FMS). We lack evidence of the role of vitamin D supplementation in these patients.

Reliability of isometric strength measurements in trunk and neck region: patients with chronic neck pain compared with pain-free persons.

Objective: Evaluation of reliability of isometric strength measurements in the neck and trunk region and comparison of these measurements between patients with chronic neck pain and pain-free subjects.

Design: Nonrandomized controlled trial.

Setting: Institutional practice.