It is concluded that exposition of subjects to sunlight, type of food, and a family history of headache had most significant effects on occurrence of migraine and tension-type headaches.

This paper aims to identify the features of a natural dentition, specifically the number and distribution of teeth, which are important for oral satisfaction and freedom from eating problems in the elderly. Data were gathered on the dental condition, satisfaction and function of 1211 dentate adults aged 60 years or over, randomly sampled from three areas in England. Multiple logistic regression was used to identify the clinical factors which contribute to satisfaction with aesthetics and the ability to bite and chew. Satisfaction with biting and chewing was influenced by specific reported eating problems, dry month and increasing age. The presence of these eating problems was related to a complex series of factors describing the number and distribution of teeth and dentures, and some variables describing symptoms and disease. Having 21 or more natural teeth and no removable partial dentures (odds ratio 3.2), 2 or more posterior contacting pairs of teeth (odds ratio 1.7), and few anterior spaces were important factors related to the absence of eating problems. Unfilled anterior spaces (odds ratio 3.9), and widespread caries and periodontal disease were associated with aesthetic dissatisfaction. Many of the principles of shortened dental arch are consistent with good function and satisfaction in the elderly.

BackgroundIn clinical trials, both unequal randomization design and sequential analyses have ethical and economic advantages. In the single-stage-design (SSD), however, if the sample size is not adjusted based on unequal randomization, the power of the trial will decrease, whereas with sequential analysis the power will always remain constant. Our aim was to compare sequential boundaries approach with the SSD when the allocation ratio (R) was not equal.MethodsWe evaluated the influence of R, the ratio of the patients in experimental group to the standard group, on the statistical properties of two-sided tests, including the two-sided single triangular test (TT), double triangular test (DTT) and SSD by multiple simulations. The average sample size numbers (ASNs) and power (1-β) were evaluated for all tests.ResultsOur simulation study showed that choosing R = 2 instead of R = 1 increases the sample size of SSD by 12% and the ASN of the TT and DTT by the same proportion. Moreover, when R = 2, compared to the adjusted SSD, using the TT or DTT allows to retrieve the well known reductions of ASN observed when R = 1, compared to SSD. In addition, when R = 2, compared to SSD, using the TT and DTT allows to obtain smaller reductions of ASN than when R = 1, but maintains the power of the test to its planned value.ConclusionThis study indicates that when the allocation ratio is not equal among the treatment groups, sequential analysis could indeed serve as a compromise between ethicists, economists and statisticians.

A random sample of 2280 subjects aged 60 years or over from three areas of England were examined clinically in order to assess their dental health and needs. Between 33% (south of England) and 57% (north of England) were edentulous. Twenty per cent of all dentate subjects were edentulous in one arch and thus still required a complete denture. Amongst the dentate subjects geographical differences were small, but social class and behavioural differences were large. Dental non-attenders were the group who stood out as having much poorer oral health, averaging six fewer natural teeth than attenders. Nearly 50% of all teeth either had coronal fillings or needed them. Root caries was common, 20-22% of vulnerable teeth were affected and there was an age related increase in disease risk. The mean number of teeth with decayed roots per subject (0.8) was similar to the mean number with decayed coronal surfaces (0.9). Moderate tooth wear and moderate periodontal disease were both widespread. A minority of subjects had a functional dentition of 21 or more teeth. Major changes in the dental status of older adults have taken place in the last 30 years and these will continue, resulting in lower levels of edentulousness but a large need for maintenance of existing restorations.

BackgroundItem response theory (IRT) is extensively used to develop adaptive instruments of health-related quality of life (HRQoL). However, each IRT model has its own function to estimate item and category parameters, and hence different results may be found using the same response categories with different IRT models. The present study used the Rasch rating scale model (RSM) to examine and reassess the psychometric properties of the Persian version of the PedsQLTM 4.0 Generic Core Scales.MethodsThe PedsQLTM 4.0 Generic Core Scales was completed by 938 Iranian school children and their parents. Convergent, discriminant and construct validity of the instrument were assessed by classical test theory (CTT). The RSM was applied to investigate person and item reliability, item statistics and ordering of response categories.ResultsThe CTT method showed that the scaling success rate for convergent and discriminant validity were 100% in all domains with the exception of physical health in the child self-report. Moreover, confirmatory factor analysis supported a four-factor model similar to its original version. The RSM showed that 22 out of 23 items had acceptable infit and outfit statistics (<1.4, >0.6), person reliabilities were low, item reliabilities were high, and item difficulty ranged from -1.01 to 0.71 and -0.68 to 0.43 for child self-report and parent proxy-report, respectively. Also the RSM showed that successive response categories for all items were not located in the expected order.ConclusionsThis study revealed that, in all domains, the five response categories did not perform adequately. It is not known whether this problem is a function of the meaning of the response choices in the Persian language or an artifact of a mostly healthy population that did not use the full range of the response categories. The response categories should be evaluated in further validation studies, especially in large samples of chronically ill patients.

Background:Body weight is made up of lean and fat mass and both are involved in growth and development. Impression of these two components in bone density accrual has been controversial.Objectives:The aim of this study was to evaluate the relationship between fat and lean mass and bone density in Iranian children and adolescents.Patients and Methods:A cross-sectional study was performed on 472 subjects (235 girls, 237 boys) aged 9-18 years old in Fars Province. The participants' weight, height, waist circumference, stage of puberty, and level of physical activity were recorded. Bone Mineral Content (BMC), Bone Mineral Density (BMD), total body fat and lean mass were measured using dual-energy X-ray absorptiometry.Results:Results showed that 12.2% of boys and 12.3% of girls were overweight and 5.5% of boys and 4.7% of girls were obese. Obese individuals had greater total body BMD (0.96 ± 0.11) than normal-weight ones (0.86 ± 0.11) (P < 0.001). We found the greatest correlation between total body BMD and total body lean mass (R = 0.78. P < 0.001) and the least correlation with total body fat percentage (R = 0.03, P = 0.44). Total lean mass in more active boys was 38.1 ± 10.9 and in less active boys was 32.3 ± 11.0 (P < 0.001). The results of multiple regression analysis showed that age and total body lean mass were independent factors of BMD in growing children and adolescents.Conclusions:These findings suggest that lean mass was the most important predictor of BMD in both genders. Physical activity appears to positively impact on lean mass and needs to be considered in physical education and health-enhancing programs in Iranian school children.

SummaryThe prevalence of overweight and obesity in most developed and developing countries have been increasing markedly over the past two decades. This increase includes all ages, genders, racial and ethnic groups, income, and educational levels. This study examined the prevalence of overweight and obesity among adults aged 25-55 years in Shiraz (Southern Iran). The data are based on a random multistage sample survey of 2282 married adults (1141 pairs) living is Shiraz, whose heights and weights were measured in the 2002-2003 academic year. The prevalence of overweight or obesity (body mass index Ն 25) was 49.7% in men and 63.9% in women. The prevalence of obesity (body mass index Ն 30) was 10.5% and 22.5% in men and women, respectively, which shows an increased secular change of 5.8% in men and 17.4% in women during a 14-year period. Overweight and obesity are common in Iran. Obesity and overweight were significantly more common among women than among men (P-valve = 0.000). There is a need to establish programmes for prevention and treatment of obesity especially Iranian's women.

PCS with its large scale and wealth of socio-economic and medical data can be a unique platform for studying the etiology of non-communicable diseases and effective interventions in Iran.