Table 1. Clinical Studies.

Author	Groups Studied and Intervention	Results and Findings	Conclusions
J.F. de Carvalho, et al80	11 female patients were given 50,000 IU oral vitamin D supplementation weekly for 3 months to assess the effect on FM symptoms. Endpoints were measured using TPC and VAS to assess pain.	At the end of the 3-month period, VAS scores decreased from 90 to 30 (p=0.002) and TPC decreased from 17 to 10 (p=0.07).	The study concluded that disease symptoms of FM seemed to improve with vitamin supplementation.
F. Wepner, et al79	30 women with FM were evenly divided into a TG and CG. The treatment group was given vitamin D supplementation for 20 weeks with the goal of achieving a serum vitamin D level between 32 and 48 ng/mL. The CG was given a placebo. Endpoints were measured using VAS for pain, SF-36, Anxiety and Depression Scale, and FIQ.	Significant improvements were seen in the TG in VAS pain scores and physical role functioning scale of the SF-36.	The study concluded that adequate vitamin D levels in FM patients had a positive effect on the perception of pain.
R. Yilmaz, et al81	58 patients with chronic widespread musculoskeletal pain, including those with FM, were treated with 50,000 IU/week of Vitamin D supplementation for 3 months. Endpoints were measured using serum levels of Ca, P, ALP, vitamin D, VAS for pain and asthenia, BDI, SF-36, TPC, and several others.	At the end of 3 months, patients showed decreased in VAS for pain and asthenia, severity of waking unrefreshed, TPC, and BDI.	The study concluded that vitamin D supplementation in those with CWMP, including those with FM, showed improvements in musculoskeletal symptoms, level of depression, and quality of life. It also stated that patients with CWMP should be screened for Vitamin D deficiency.
A. Mirzaei et al82	74 patients with FM were equally and randomly separated in a CG and TG. The TG was given 50,000 IU/week of oral Vitamin D and 25 mg of trazodone nightly for 8 weeks. The CG received the trazadone along with a placebo. Endpoints were measured using WPI, FIQ, PSQI, and SF-36.	At the end of 8 weeks, improvements in WPI< FIQ and PSQI scores were seen in both groups. Improvement in WPI and the physical component score of the SF-36 were more prominent in the TG. Overall scores on the SF-36 showed improvement in the TG compared to the CG.	The study concluded that vitamin D supplementation was useful in decreasing pain in FM patients. Supplementation of vitamin D combined with an antidepressant reportedly amplified the improvement in physical and psychological symptoms.
S. Abou-Raya et al83	72 FM patients were evenly and randomly distributed into a TG and CG. The TG received 2,000 IU/day of oral Vitamin D for 6 months. The CG received a placebo. Endpoints were measured using FIQ, BPI, BDI, VAS for pain, and SF-36.	At 6 months, results showed a decrease in VAS pain scores (p<0.001). There were also improvements in SF-36 and FIQ scores (p<0.005).	The study concluded that vitamin D supplementation had a positive effect on pain perception in FM patients.

Abbreviations: International Unit (IU); fibromyalgia (FM); tender point count (TPC); visual analog score (VAS); treatment group (TG); control group (CG); Fibromyalgia impact questionnaire (FIQ); 36-item Short Form Health Survey (SF-36); calcium (Ca); phosphate (P); alkaline phosphatase (ALP); Beck Depression Inventory (BDI); chronic widespread musculoskeletal pain (CWMP); Widespread Pain Index (WPI); Pittsburgh Sleep Quality Index (PSQI); Brief Pain Inventory (BPI)