Patient’s demographics and basic characteristics
| Characteristics | Total N=144 | Coeliac disease N=86 | Without coeliac disease N=58 |
| Male, n (%) | 55 (38) | 27 (31) | 28 (48) |
| Female, n (%) | 89 | 59 (69) | 30 (52) |
| Age (years), md (IQR) | 48.5 (31–62) | 40 (24–50) | 47.5 (33–62) |
| Ethnicity | |||
| European, n (%) | 84 (58) | 60 (70) | 24 (41) |
| Asian, n (%) | 32 (22) | 18 (21) | 14 (24) |
| Pasifika, n (%) | 16 (11) | 5 (6) | 11 (19) |
| Maori, n (%) | 11 (8) | 3 (3) | 8 (14) |
| African, n (%) | 1 (1) | 0 | 1 (2) |
| Indications for coeliac investigations | |||
| Iron-deficiency anaemia, n (%) | 52 (36) | 36 (42) | 16 (28) |
| Diarrhoea, n (%) | 34 (23.5) | 21 (24) | 13 (22) |
| Abdominal pain/bloating, n (%) | 34 (23.5) | 14 (16) | 20 (34) |
| Weight loss, n (%) | 24 (17) | 15 (17) | 9 (16) |
| Visual impression on gastroscopy | |||
| Normal, n (%) | 70 (49) | 23 (27) | 47 (81) |
| Villous flattening, n (%) | 35 (24) | 31 (36) | 4 (7) |
| Scalloping, n (%) | 28 (19) | 27 (31) | 1 (2) |
| Erythema, n (%) | 11 (8) | 5 (6) | 6 (10) |
| Duodenal histology | |||
| Normal, n (%) | 58 (40) | 0 | 58 |
| Marsh I, n (%) | 9 (6) | 9 (10.5) | 0 |
| Marsh II, n (%) | 9 (6) | 9 (10.5) | 0 |
| Marsh III, n (%) | 68 (47) | 68 (79) | 0 |
| Serology to biopsy time (days), md (IQR) | 129 (39–209) | 139 (35–208) | 120 (47–252) |
| Number of biopsies, md (IQR) | 5 (5–6) | 5 (4–6) | 5 (3–6) |
| Anti-TTG IgA U/mL, md (IQR) | 87 (31–250) | 250 (109–300) | 30 (24–50) |
IQR, interquartile range; md, median; n, number.