Characteristics of cases and controls and details of their thermal environment
| HSES cases (n = 31) | Controls (n = 124) | |
|---|---|---|
| Age in weeks (mean (SD)) | 15.4 (6.0) | 15.3 (6.0) |
| Boys | 18 (58) | 67 (54) |
| Social class | ||
| I/II | 5 (17) | 49 (41) |
| IIINM/IIIM | 11 (38) | 45 (38) |
| IV/V | 13 (45) | 26 (22) |
| Outside temperature in °C (mean (SD)) | 9.2 (4.1) | 9.2 (4.1) |
| Duration of room heating | ||
| None | 11 (35) | 29 (23) |
| Until baby was put down | 3 (10) | 47 (38) |
| Part of night | 7 (23) | 32 (26) |
| All of night | 10 (32) | 16 (13) |
| Duration of heating baby’s cot | ||
| None | 29 (94) | 114 (92) |
| Until baby was put down | 2 (6) | 8 (6) |
| Part of night | 0 (0) | 1 (1) |
| All of night | 0 (0) | 1 (1) |
| Main type of bedding | ||
| No bedding | 1 (3) | 1 (1) |
| Blankets | 7 (23) | 49 (40) |
| Duvet (with or without blankets) | 22 (71) | 73 (59) |
| Baby nest or sleeping bag | 1 (3) | 1 (1) |
| Swaddled | 9 (29) | 21 (17) |
| Total insulation in togs (mean (SD)) | 9.8 (3.2) | 8.1 (3.5) |
| Degree of covering by bedding | ||
| Completely uncovered | 2 (6) | 17 (14) |
| Head uncovered, body partly covered | 6 (19) | 54 (44) |
| Head uncovered, body wholly covered | 14 (45) | 41 (33) |
| Head partly or wholly covered, body covered | 9 (29) | 11 (9) |
| Hat worn | 0 (0) | 2 (2) |
| Amount of sweating while asleep | ||
| None | 20 (65) | 98 (79) |
| Slight | 2 (6) | 16 (13) |
| Moderate | 5 (16) | 7 (6) |
| Profuse | 4 (13) | 3 (2) |
| Parents’ estimate of baby’s temperature while asleep | ||
| Below normal | 1 (4) | 1 (1) |
| Normal | 23 (85) | 107 (86) |
| Slightly raised | 2 (7) | 16 (13) |
| High | 1 (4) | 0 (0) |
| Signs of infection in baby in previous 24 hours | 12 (39) | 36 (29) |
| Infection in other members of household in previous five days | 12 (39) | 56 (45) |
| Baby sleeping in parents’ bed | 1 (3) | 2 (2) |
Values are n (%) unless otherwise stated.
NM, non-manual; M, manual.