|
| Study | Reason for exclusion |
|
| Sibulesky et al. [7] | Secondary analysis assessing the safety of long-term vitamin A supplementation in an RCT for RP [9, 17]. No fundus index. |
| Zorge et al. [25] | Not randomized. A cohort of RP patients and patients with related retinal degenerations followed prospectively before and after administration of lutein. No control group. |
| Aleman et al. [26] | Not randomized. Patients with the diagnosis of RP or Usher syndrome and normal subjects; a subset of 23 patients with retinal degeneration and 8 normal subjects participated in a 6-month pilot trial of lutein supplementation. No placebo control group and no attempt to mask the patient as to the content of the supplement. |
| Wheaton et al. [27] | Secondary analysis assessing the safety of long-term DHA supplementation in an RCT for X-linked RP. No fundus index. |
| Berson et al. [28] | Subgroups of patients with retinitis pigmentosa between rates of decline in ocular function, dietary ω-3 fatty acid intake and RBC PE DHA levels and whether vitamin A intake was associated with a change in RBC PE DHA levels over the duration of the study [19]. |
| Rotenstreich et al. [29] | Nonrandomized prospective pilot study, treatment of a retinal dystrophy, fundus albipunctatus, with oral 9-cis-{beta}-carotene. No control group. |
| Berson et al. [8] | Not randomized clinical trials, calculated dietary intake from 3 clinical trials conducted among patients with typical retinitis pigmentosa from 1984 to 1991 (clinical trial 1), 1996 to 2001 (clinical trial 2), and 2003 to 2008 (clinical trial 3) by questionnaires. |
| Rayapudi et al. [30] | Not randomized clinical trials, a review. |
| Hughbanks-Wh eaton et al. [31] | Safety assessment of high-dose docosahexaenoic acid (DHA) supplementation in a 4-year randomized clinical trial in X-linked retinitis pigmentosa (XLRP). No fundus index. |
| Hoffman et al. [32] | Ancillary outcomes of the DHAX Trial [24]. |
| Berson et al. [33] | No randomized control design. Retrospective, nonrandomized comparison retrospective, observational design of vitamin A, and control cohorts followed up for a mean of 4 to 5 years. |
| Clinical trials [34] | The effect of oral administration of 9-cis β-carotene-rich powder of the alga Dunaliella bardawil on visual functions in patients with RP. Recruiting. |
| Clinical trials [35] | The effect of oral administration of 9-cis β-carotene-rich powder of the alga Dunaliella bardawil on visual functions in adolescent patients with RP. Not yet recruiting. |
|
