Table 1.
Characteristics of randomised controlled trials of fibre versus placebo or no treatment in irritable bowel syndrome
| Study | Country | Setting | Diagnostic criteria for irritable bowel syndrome | Criteria to define symptom improvement after therapy | Sample size | Fibre type | Duration of therapy | Jadad score |
|---|---|---|---|---|---|---|---|---|
| Soltoft 1976w2 | Denmark | Tertiary care | Clinical diagnosis and investigations | Patient reported improvement in global symptoms | 59 | Miller’s bran 30 g per day | 6 weeks | 4 |
| Manning 1977w3 | England | Tertiary care | Clinical diagnosis and investigations | Any decrease in patient reported percentage of days with pain | 26 | Bran 20 g per day (wheat bran or whole wheat bread) | 6 weeks | 3 |
| Ritchie 1979w33 | England | Tertiary care | Clinical diagnosis and investigations | Patient reported improvement in global symptoms (doctor required to agree) | 24 | Ispaghula husk two sachets per day | 3 months | 4 |
| Longstreth 1981w9 | USA | Secondary care | Clinical diagnosis | Patient reported improvement in global symptoms | 77 | Metamucil 6.4 g per day | 8 weeks | 4 |
| Arthurs 1983w8 | Ireland | Secondary care | Clinical diagnosis | Doctor reported improvement in global symptoms | 78 | Ispaghula husk two sachets per day | 4 weeks | 4 |
| Nigam 1984w35 | India | Secondary care | Clinical diagnosis and investigations | Patient reported improvement in global symptoms (doctor required to agree) | 42 | Ispaghula husk (dose unclear) | 12 weeks | 3 |
| Kruis 1986w34 | Germany | Tertiary care | Clinical diagnosis and investigations | Patient reported improvement in global symptoms | 80 | Wheat bran 15 g per day | 16 weeks | 2 |
| Lucey 1987w7 | England | Tertiary care | Manning criteria and investigations | Any decrease in global symptom score | 28 | Wheat bran biscuits 15.6 g per day | 3 months | 3 |
| Prior 1987w6 | England | Tertiary care | Clinical diagnosis and investigations | Patient reported absence of abdominal pain | 80 | Ispaghula husk three sachets per day | 12 weeks | 4 |
| Jalihal 1990w5 | India | Secondary care | Clinical diagnosis and investigations | Patient reported improvement in global symptoms | 20 | Ispaghula husk 30 g per day | 4 weeks | 4 |
| Fowlie 1992w4 | Scotland | Tertiary care | Clinical diagnosis and investigations | Patient reported improvement in global symptoms | 49 | 4.1 g of unspecified fibre per day | 12 weeks | 4 |
| Rees 2005w1 | England | Tertiary care | Rome I criteria and investigations | Patient reported improvement in global symptoms | 28 | Wheat bran 10 to 20 g per day | 12 weeks | 1 |