Table 1.
Characteristics of studies included in the systematic review.
| First Author, Publication Year | Study Design | Year(s) | Country | Number of Participants | Sex a | Age b | Race or Ethnicity | Diagnosis c |
|---|---|---|---|---|---|---|---|---|
| Azad 2000 [21] | Intervention Control Trial |
No data | Bangladesh | 78 | Female 78% Male 22% |
30.9 (12–60) | No data | FMS |
| Correa-Rodríguez 2020 [16] | Observational, Cross-sectional | 2018 | Spain | 95 | Female 100% | 55.76 | No data | FMS |
| Donaldson 2001 [22] | Intervention Pre and Post Trial |
No data | United States | 20 | Female 93% Male 7% |
(45–54) | No data | FMS |
| Hänninen 2000 [27] | Intervention Pre and Post Control Trial |
No data | Finland | 33 | No data | 51 | No data | FMS |
| Holton 2012 [23] | Intervention Pre and Post Trial |
No data | United States | 37 | Female 92% Male 8% |
51.6 | No data | FMS and IBS |
| Lamb 2011 [18] | Intervention Cross-over Trial |
2008 | United States | 8 | Female 100% | 55.6 (48–74) | White | FMS |
| Marum 2016 [19] | Intervention Pre and Post Trial |
2015 | Portugal | 38 | Female 100% | 51 | No data | FMS and GID |
| Pagliai 2020 [25] | Intervention Cross-over Trial |
No data | Italy | 20 | Female 95% Male 5% |
48.95 | No data | FMS |
| Rodrigo 2013 [17] | Intervention Pre and Post Trial |
2007–2012 | Spain | 7 | Female 100% | 49 (34–68) | White | FMS, IBS and CD |
| Senna 2012 [26] | Intervention Control Trial |
2011 | Egypt | 83 | Female 90% Male 10% |
45.6 | No data | FMS |
| Slim 2017 [24] | Intervention Parallel-group Trial | 2012–2014 | Spain | 55 | Female 97% Male 3% |
HCD: 53 (32–65) GFD: 52 (36–66) |
No data | FMS and GS |
| Vellisca 2014 [20] | Intervention Control Trial |
No data | Spain | 72 | Female 100% | 40.98 (24–65) | No data | FMS |
a Based on 75 participants at the start of the trial for the Slim study. b Mean (range) is included; for the Donaldson study, values are from normal data range for women aged 45–54 noted in the publication [22]; for the Hänninen study, average age was estimated based on another publication of the same study [8]; and for the Slim study the median age (range) is included. c ACR 1990 Criteria for Fibromyalgia Syndrome and ROME III Criteria for Irritable Bowel Syndrome were used except for Marum, Pagliai and Slim studies. Abbreviations used: celiac disease (CD), fibromyalgia syndrome (FMS), gastrointestinal disorder (GID), gluten-free diet (GFD), gluten sensitivity (GS), hypocaloric diet (HCD), and irritable bowel syndrome (IBS).