Six RCTs and 16 non-randomized interventions were included in the analysis. There was a significant decrease in IBS SSS scores for those individuals on a low FODMAP diet in both the RCTs (OR , 95 % CI -; I (2) = , p = ) and non-randomized interventions (OR , 95 % CI -; I (2) = , p = ). In addition, there was a significant improvement in the IBS-QOL score for RCTs (OR , 95 % CI -; I (2) = , p = ) and for non-randomized interventions (OR , 95 % CI -; I (2) = , p = ). Further, following a low FODMAP diet was found to significantly reduce symptom severity for abdominal pain (OR , 95 % CI -; I (2) = , p = ), bloating (OR , 95 % CI -; I (2) = , p = ) and overall symptoms (OR , 95 % CI -; I (2) = , p = ) in the RCTs. In the non-randomized interventions similar findings were observed.
Mood and other symptoms were evaluated by participant self-report using the Atkins Health Indicator Test (AHIT) in individuals undergoing weight loss following either a low-carbohydrate, ketogenic diet (LCKD) or a low-fat diet (LFD). Participants were 119 overweight community volunteers randomized to an LCKD or an LFD. An additional 51 participants who had completed an earlier trial contributed data for the psychometric analyses but were not included in the prospective analyses. Self-reported symptom levels on seven scales factor-analytically derived from the AHIT (negative affect, fatigue, somatic symptoms, physical effects of hunger, insomnia, hunger, and stomach problems) were acquired during 12 visits.
A sign has the potential to be objectively observed by someone other than the patient, whereas a symptom does not. There is a correlation between this difference and the difference between the medical history and the physical examination . Symptoms belong only to the history, whereas signs can often belong to both. Clinical signs such as rash and muscle tremors are objectively observable both by the patient and by anyone else. Some signs belong only to the physical examination, because it takes medical expertise to uncover them. (For example, laboratory signs such as hypocalcaemia or neutropenia require blood tests to find.) A sign observed by the patient last week but now gone (such as a resolved rash) was a sign, but it belongs to the medical history, not the physical examination, because the physician cannot independently verify it today.