Table 3. Indian studies looking at serum 25(OH)D in outdoor workers.

Study	Year, place	Mean serum 25(OH)D in ng/mL
Rajasree et al. [18]	1999, Thiruvananthapuram	169.8 (laborers), 110.2 (fishermen)
Goswami et al. [16]	2017, New Delhi	29.0 ± 8.61
Dharmshaktu et al. [17]	2019, New Delhi	17.92 ± 7.84
Present study	December 2019, Kolkata	21.79 ± 6.31