Epidemic and population patterns in the Chinese Empire (243 B.C.E. to 1911 C.E.): quantitative analysis of a unique but neglected epidemic catalogue.

A catalogue of dates and places of major outbreaks of epidemic diseases, that occurred in the Chinese Empire between 243 B.C.E. and 1911 C.E., combined with corresponding demographic data, provides a unique opportunity to explore how the pressure of epidemics grew in an agrarian society over 2000 years. This quantitative analysis reveals that: (1) the frequency of outbreaks increased slowly before the 12th century and rapidly thereafter, until 1872; (2) in the first millennium of our era, the people of China lived for decades free of major epidemics; in the second millennium, major outbreaks occurred every couple of years, but were localized; (3) in the more recent centuries, these outbreaks were as common, but disseminated to more places. This evolution, closely matching the demographic growth, was similar in the north and south of China, and therefore may have been similar in other regions of the world.

Validation of questionnaire-based response criteria of treatment efficacy in the fibromyalgia syndrome.

OBJECTIVE: To compare the validity of self-reported questionnaires as response criteria of treatment efficacy in patients with fibromyalgia syndrome. METHOD: At the beginning of the treatment period, 70 fibromyalgia patients, randomly allocated to electro-acupuncture or placebo, underwent a clinical evaluation by rheumatologists and answered 1) a generic quality of life questionnaire--the Psychological General Well-Being Index (PGWB), 2) a specific function and symptom questionnaire, and 3) a pain questionnaire--the Regional Pain Score (RPS). The same evaluation was repeated at the end of the treatment period. Severity of the condition was assessed by a composite outcome score, a combination of different clinical outcome measures forming a clinical severity index. The variations between these questionnaire scores before and after treatment and the variations between the clinical severity indices estimated by clinicians were used as measures of the treatment impact. The first rationale for the validation was a positive correlation between clinical and questionnaire score changes. Another rationale for validation of the new instruments was the ability to identify the different treatment interventions. RESULTS: The correlation between the clinical severity index and the RPS was good (r = 0.62). Moreover, the RPS demonstrated a good discriminant power in detecting patients with effective treatment: it showed a specificity of 74% and a sensitivity of 75%. The PGWB correlated less well with the clinical score and was less discriminant. The specific function and symptom questionnaire showed little additional validity. CONCLUSIONS: Outcomes of syndrome severity such as pain and subjective well-being, as measured by self-reported questionnaires, can be valid instruments to evaluate treatment efficacy in short-term clinical trials. In the current study, the RPS proved to be particularly useful to assess the widespread tenderness of fibromyalgia and demonstrated high discriminative power.

Is intrapartum vibratory acoustic stimulation a valid alternative to fetal scalp pH determination?

OBJECTIVES: To determine the association between fetal heart rate accelerations, whether spontaneous or induced by vibratory acoustic stimulation, and subsequent scalp pH values in presence of a suspicious intrapartum fetal heart rate tracing, and thereby assess the ability of accelerations to predict a concurrent normal fetal scalp blood pH. DESIGN: Prospective observational study of 253 labours involving 421 pH samples. SETTING: Tertiary care university hospital of Genoeva. INTERVENTION: Vibratory acoustic stimulation through the maternal abdominal wall for five seconds prior to fetal blood sampling. MAIN OUTCOME MEASURES: Spontaneous fetal heart rate reactivity (accelerations) in the 10 min preceding vibratory acoustic stimulation, vibratory acoustic-induced reactivity prior to fetal blood sampling, and scalp pH value. RESULTS: The positive predictive value of a reactive fetal heart rate response after vibratory acoustic stimulation was 78% (95% CI 73-84%) and 97% (95% CI 94-99%) for scalp pH values of > 7.25 and > or = 7.20, respectively. Similar observations occurred with spontaneous reactivity. Of concern, 7 out of 31 (23%) occasions where the scalp blood pH was less than 7.20 appeared to be associated with a normal fetal heart rate response to vibratory acoustic stimulation. CONCLUSION: Fetal heart rate acceleration induced by vibratory acoustic stimulation was significantly associated with a normal scalp blood pH higher than 7.25. However, vibratory acoustic stimulation offers no advantage over observation of spontaneous fetal heart rate tracings and cannot safely replace fetal blood sampling during labour.

Dietary habits of smokers, people who never smoked, and exsmokers.

A large database on hospital patients with illnesses not related to tobacco or alcohol was used to investigate the dietary habits of males and females who never smoked, who were exsmokers, and who currently smoked. Smoking was positively related to meat consumption and negatively related to cereal consumption in males. Both male and female smokers consumed fewer vegetables and fruits but more alcohol and coffee than did people who never smoked. Exsmokers' diets were similar to those of people who never smoked. These results emphasize the importance of ruling out potential confounders or effect modifiers when studying the role of meat, milk, fruits, vegetables, cereal, coffee, or alcohol intake in the etiology of tobacco-related diseases.

Reproducibility of food frequency measurements and inferences from a case-control study.

To investigate the relationship between the reproducibility of measurements of exposure from a frequency questionnaire and inferences from a case-control study, 229 patients were reinterviewed on the telephone an average of 6 weeks after the original interview. Several indices of agreement were computed. Information on smoking and use of alcohol and coffee was quite reproducible, as reflected by most measures of agreement, using grouped or continuous data. Frequency of meat, vegetable, and fruit intake had low reproducibility. For all variables, reproducibility was similar for cases and controls. Reproducibility of the exposure variables was a good predictor of the reproducibility of the relative odds (RO) obtained with the first and the repeat interviews. Lack of reliability of the exposure variable appeared to produce fluctuations in the ROs in either direction, even though the same degree of agreement was observed for cases and controls. This situation may partially explain discrepant findings between case-control studies of diet and chronic diseases.

Diet and opiate addiction: a quantitative assessment of the diet of non-institutionalized opiate addicts.

The diet, weight and height of 38 non-institutionalized chronic opiate addicts have been assessed and compared to those of a random sample of the 20-35 year old general population of Canton Geneva, Switzerland. A history questionnaire was administered by specially trained dietitians. Results show that, after adjustment for age and alcohol intake, male addicts have the same caloric intake as non-addicts. However, addicts tend to replace foods that are rich in fat and proteins with foods rich in sucrose and relatively poor in vitamins and minerals. Beer is the major component of their much larger alcohol consumption. On the other hand, the body mass index (kg/m2) of the male addicts is within the normal range, suggesting this may not be a good indicator of their unbalanced diet. This study gives a quantitative assessment, in terms of nutrient intake, of the typical craving for sweet described by opiate addicts.