Table 1 Patient demographics

Characteristic		Patients with TSH within reference range N = 15, n (%)	Patients with TSH lower than reference range N = 7, n (%)	Patients with TSH higher than reference range N = 5, n (%)
Sex	Female	11 (73)	4 (57)	3 (60)
Sex	Male	4 (27)	3 (43)	2 (40)
Location	Rural	6 (40)	6 (86)	1 (20)
Location	Urban	9 (60)	1 (14)	4 (80)
Age, years	30–39	1 (7)	1 (14)	2 (40)
	40–49	1 (7)	1 (14)	1 (20)
	50–59	0 (0)	0 (0)	1 (20)
	60–69	8 (53)	3 (43)	1 (20)
	70–79	3 (20)	1 (14)	0 (0)
	80–89	2 (13)	1 (14)	0 (0)
Years with hypothyroidism	≤5	2 (13)	1 (14)	3 (60)
	6–10	2 (13)	4 (57)	0 (0)
	11–20	5 (33)	1 (14)	2 (40)
	>20	6 (40)	1 (14)	0 (0)
Other relevant health conditions	Coeliac disease	0 (0)	0 (0)	0 (0)
	Pernicious anaemia	2 (13)	0 (0)	0 (0)
	Gastrointestinal (gallstones/diverticulitis/irritable bowel syndrome/twisted bowel/constipation)	4 (27)	2 (29)	2 (40)
	Type 2 diabetes	3 (20)	0 (0)	0 (0)
Other relevant medications	Calcium-containing drugs	3 (20)	0 (0)	1 (20)
	Iron-containing drugs	0 (0)	1 (14)	1 (20)
	Proton pump inhibitors	3 (20)	1 (14)	1 (20)
BMI	<20	1 (7)	0	0
	20–25	5 (33)	1 (14)	2 (40)
	26–30	5 (33)	5 (71)	2 (40)
	31–35	3 (20)	1 (14)	1 (20)
	36–40	1 (7)	0	0
Daily levothyroxine dose, µg	25	1 (7)	0	0
	50	1 (7)	0	0
	75	2 (13)	0	0
	100	3 (20)	2 (29)	2 (40)
	125	3 (20)	2 (29)	3 (60)
	150	2 (13)	0	0
	175	0 (0)	0	0
	200	0 (0)	0	0
	225	0 (0)	1 (14)	0
	100/125 alternate day dosing	1 (7)	1 (14)	0
	100/75 alternate day dosing	0 (0)	1 (14)	0
	100 Monday–Friday, 75 Saturday–Sunday	2 (13)	0	0