Analysis of 239 consecutive diabetic patients, 97 taking vitamin D supplements, showing significantly higher vitamin D levels in supplemented patients. There was no statistically significant difference in cases based on supplementation, with only 3 cases total.
This study is excluded in the after exclusion results of meta
analysis: 
very few events; unadjusted results with no group details; minimal details provided.
| 
risk of case, 26.8% lower, RR 0.73, p = 1.00, treatment 1 of 97 (1.0%), control 2 of 142 (1.4%), NNT 265.
 | 
| Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates | 
 
Lázaro et al., 5 Sep 2021, retrospective, Spain, preprint, 9 authors, dosage not specified.
 
DOI record:
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      "family": "Santana-Suarez",
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      "family": "Quintana-Arroyo",
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    {
      "affiliation": [],
      "family": "Acosta-Calero",
      "given": "Carmen",
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    {
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      "family": "Arnás",
      "given": "León Claudia",
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      "family": "Javier",
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  "subtitle": [],
  "title": "Vitamin D deficit in type 2 diabetes patients during COVID-19 lockdown with and without supplementation",
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