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C Osmond

Publications and source records attributed to C Osmond.

At least 163 records · Page 9Linked to original sources
PubMed1989

Comparison of a food frequency questionnaire with a diet record.

The associations between levels of nutrients derived from a 24-hour diet record and a food frequency questionnaire were assessed in a sample of 433 men and women. The food frequency questionnaire was administered three years after the completion of the diet record. Spearman correlations were all statistically significant; they varied from 0.36 for energy to 0.15 for vitamin A. Comparison of distributions into fifths showed few people grossly misclassified. A model was developed to assess the correlations which would be expected under various conditions of within and between subject variance for each nutrient, errors in measurements and drift in intake over time. The best possible correlation that could be obtained using the within and between subject variations in intake previously published, and with no measurement error or drift over time, was 0.60 for energy and 0.34 for vitamin A. Using a realistic measure of measurement error (standard deviation on log scale of 0.12 for diet record method, 0.06 for drift over time and 0.18 for food frequency method) the correlations obtained in the modelling were very similar to that observed. This study shows that it may be appropriate to use a food frequency questionnaire instead of a diet record to estimate intakes in population based epidemiological studies.

Adult↗
PubMed1989

Iodine supplementation with oral or intramuscular iodized oil. A two-year follow-up of a comparative trial.

A controlled trial of iodine supplementation comparing oral with intramuscular iodized oil has been carried out in an iodine deficient area of Zaire. Two years after the administration of 2 ml of oral iodized oil to the population of four villages the overall goitre prevalence had fallen from 64 to 54%. In a further two villages given 2 ml of intramuscular oil the prevalence fell from 65 to 50%. The effectiveness of supplementation was also assessed by measuring changes in thyroid function in women of reproductive age. Among women in the villages given oral iodized oil, the geometric mean thyroxine concentration, measured in dried bloodspots, rose from 27.2 to 52.6 nmol/L at the two-year follow-up. This was similar to the response of the intramuscularly treated villages in which thyroxine levels rose from 32.1 to 65.4 nmol/L. There was no change in goitre prevalence or thyroid function in two control villages. Oral iodized oil is a cheaper and simpler alternative to the injected form providing effective iodine prophylaxis for up to two years after a single dose.

Administration, Oral↗
PubMed1989

Analysis of the household distribution of trachoma in a Gambian village using a Monte Carlo simulation procedure.

Studies on the household distribution of trachoma have reached conflicting conclusions. This paper describes a cross-sectional survey of endemic trachoma in a Gambian village. Cases of active trachoma were mapped, and the compound and household distribution of the disease analysed by a Monte Carlo simulation procedure which takes into account differences in the size and age distribution within individual households. Significant clustering of active trachoma cases both by village compound (p less than 0.0001) and bedroom (less than 0.05) were detected supporting the concept that intra-familial transmission of trachoma is important. There was no evidence of spatial clustering of rooms with higher than expected prevalence of trachoma. Clustering of disease in space or time provides important evidence of infectious aetiology and route of transmission. The methods discussed here are generally applicable in the study of other infectious diseases.

Adolescent↗
PubMed1989

Age, period, and cohort models. Non-overlapping cohorts don't resolve the identification problem.

Age, period, and cohort models have generally been applied to rates from tabulated national statistics, and it is known that such models suffer from an identification problem. When individual records, including date of birth, are available, however, a unique solution has been proposed which uses non-overlapping cohorts. We have shown that the identification problem exists in continuous time, so that even perfect information on the three variables will fail to resolve it. It is important to recognize clearly the assumptions that are implicit in the non-overlapping cohort formulation of the age-period-cohort model. The value of the solution proposed depends critically on their appropriateness or otherwise. It should always be remembered that the assumptions determine much of the final solution, including the apportionment of trend to the different components, age, period, or cohort.

Age Factors↗
PubMed1989

The intrauterine and early postnatal origins of cardiovascular disease and chronic bronchitis.

Geographical differences in mortality from cardiovascular disease and chronic bronchitis within England and Wales are closely related to past differences in infant mortality. This paper examines the separate relations of mortality during 1968-78 with neonatal and post-neonatal mortality during 1911-25. These divisions of infant mortality are indicators of the intrauterine and early postnatal environments respectively. Stroke is related to neonatal mortality and therefore to the intrauterine environment. Prenatal determinants of blood pressure levels may be one mechanism underlying this. Bronchitis is related to postnatal mortality and therefore to the postnatal environment. This may reflect the long term effects of lower respiratory tract infection in early childhood. Ischaemic heart disease is related to both neonatal and post-neonatal mortality and therefore to the intrauterine and postnatal environments. The links may include blood pressure and as yet unknown processes established in early postnatal life.

Bronchitis↗
PubMed1989

Does infection initiate Graves disease? A population based 10 year study.

In order to detect whether micro-organisms could initiate the autoimmune process in Graves' disease we have studied the temporal and spatial distribution of 857 cases of hyperthyroidism occurring in a community over ten years. Cases were identified through biochemistry laboratory records and following the exclusion of patients with toxic nodular goitre or with insufficient clinical data there were 599 with Graves' disease--an average annual incidence of 15.9 per 100,000. There was a tendency for cases to present in the summer months. The reported onset of symptoms, however, peaked in December and June. There was no evidence of clustering of cases in space and time using two different statistical methods. Incidence rates doubled between 1976 and 1980 and then declined--a trend that could neither be explained by changes in laboratory or clinical diagnosis nor did it correlate with any pattern of microbial disease in the area. We conclude that it is unlikely that infections that behave in an epidemic manner have a causative role in triggering Graves' disease.

Adolescent↗
PubMed1989

Occupational causes of low-back pain.

Associations between occupational activities and low-back pain (LBP) were examined in a retrospective postal survey of 545 randomly selected adults. Each subject gave a lifetime occupational history on six specified physical activities and also a lifetime history of LBP. Among the 436 subjects answering the questionnaire, the lifetime incidence of LBP was 63%. The occurrence of LBP was related by Cox's proportional hazards regression model to occupational activities in the year prior to the onset of symptoms. For the men the strongest associations were with heavy lifting and prolonged car driving. There was also an association with heavy lifting among the women. These risks were exaggerated in the subset of subjects whose LBP followed a chronic unremitting course. The findings are consistent with previous reports linking LBP with manual materials handling and driving at work. However, in this sample, less than 20% of the cases could be attributed to such activities.

Adult↗
PubMed1988

Motoneuron disease and past poliomyelitis in England and Wales.

Past notification rates for poliomyelitis show a close geographical relation with current mortality from motoneuron disease in England and Wales. The increasing rate of poliomyelitis during the first half of this century and its predilection for affluent places and families were unique amongst infectious diseases. The unusual epidemiology of poliomyelitis is now being paralleled by motoneuron disease. These observations provide new evidence for a causal connection between the two conditions.

Cause of Death↗
PubMed1988

Acute appendicitis and bathrooms in three samples of British children.

The occurrence of appendicectomy in three national samples of British children was analysed in relation to household amenities, crowding in the home, and social class. The risk of having the operation depended on the amenities present in the home, in particular whether or not there was a bathroom. This risk was independent of social class. The findings support a relation between acute appendicitis and Western hygiene, which would explain the geographical distribution of the disease and its changing incidence over time. In the developing world, where children grow up in conditions of poor hygiene, there may be outbreaks of appendicitis when housing improves.

Acute Disease↗
PubMed1988

Iodine supplementation: comparison of oral or intramuscular iodized oil with oral potassium iodide. A controlled trial in Zaire.

A community-based controlled trial of iodine supplementation comparing oral or intramuscular iodized oil with oral potassium iodide has been carried out in 23 severely iodine-deficient villages in Eastern Zaire. The overall goitre prevalence in the population (n = 5999) was 61% and mean urinary iodine excretion in sample of 57 women 10.9 (SD 6.8) micrograms/g creatinine. All adults in three groups of four villages were given single doses of potassium iodide of 0.5 g, 1.0 g, and 2.0 g respectively. A fourth group was given oral iodized oil (2 ml) and a fifth placebo-treated. A further three villages were given intramuscular iodized oil (2 ml). The effectiveness of supplementation was assessed by measurements of bloodspot thyroxine (T4) concentration in women of reproductive age in the villages. The effects of iodide were small and inconsistent. Eight months after supplementation with oral iodized oil the distribution of T4 concentrations was similar to that seen with intramuscular oil. We conclude that oral iodized oil is an effective alternative to injected oil and would be feasible for iodine supplementation in remote areas with untrained people.

Administration, Oral↗
PubMed1988

Seasonality in the sudden infant death syndrome.

Distinctive epidemiological features of the sudden infant death syndrome (SIDS) are its age at death distribution and pronounced winter excess. Whether or not these effects are independent of the month of birth of the infant is uncertain. We used a loglinear model to separate the effects of age at death, month of death and month of birth amongst 6229 infants who died from SIDS in England and Wales during the period 1979-1983. The results suggest that month of birth and month of death independently influence the risk of the infant dying from SIDS, the risk related to month of death being much greater.

Age Factors↗
PubMed1988

A prospective study of acute idiopathic neuropathy. I. Clinical features and their prognostic value.

A prospective study in South-East England during 15 months in 1983-1984 recruited 100 patients with acute idiopathic neuropathy. After 12 months 67% had recovered completely, 20% were still significantly disabled and 13% had died. Ten of the 13 deaths were attributable to the neuropathy. The major features in the initial assessment which were associated with persistent disability were the time taken to become bedbound, requirement for ventilation, age greater than 40 years, and small or absent compound abductor pollicis brevis muscle action potentials elicited by stimulation of the median nerve at the wrist. These four variables have been combined in a statistical model to predict outcome for individual patients with acute idiopathic neuropathy.

Adolescent↗
PubMed1988

Small feet and Perthes' disease. A survey in Liverpool.

There is a high incidence of Perthes' disease among the children of unskilled manual workers in underprivileged urban areas in Britain. The skeletal measurements of 38 Liverpool children with Perthes' disease were compared with those of their siblings and of normal children from the inner and outer city. Children in families where Perthes' disease occurs have retarded growth of the trunk, with reduced sitting height and bi-acromial diameter. Among those who develop the disease there is also retarded limb growth, most evident as unusually small feet.

Anthropometry↗
PubMed1987

Death rates from stroke in England and Wales predicted from past maternal mortality.

Geographical differences in maternal mortality in England and Wales during 1911-4 correlate closely with death rates from stroke in the generation born around that time. The geographical distribution of stroke is more closely related to past maternal mortality than to any leading cause of death, past or present, except ischaemic heart disease, for which correlation coefficients with stroke are similar. This relation is new evidence that poor health and physique of mothers are important determinants of the risk of stroke among their offspring.

Aged↗
PubMed1987

Inequalities in health in Britain: specific explanations in three Lancashire towns.

The reasons why mortality is higher in the poorer areas of Britain are largely unknown. Thus how to reduce inequalities in health is a matter of conjecture. In three neighbouring towns in northern England the rates of death from all causes differ greatly. Socioeconomic conditions in the towns are similar though below average for England and Wales. The pattern of disease specific rates was analysed and related to past differences in infant mortality. It is suggested that past differences in maternal health and physique and in the postnatal environment, particularly infant feeding, housing, and overcrowding, may be determinants of current differences in adult mortality.

England↗
PubMed1987

Occupation and five cancers: a case-control study using death certificates.

A case-control approach has been used to examine mortality from five cancers--oesophagus, pancreas, cutaneous melanoma, kidney, and brain--among young and middle aged men resident in three English counties. The areas studied were chosen because they include major centres of chemical manufacture. By combining data from 20 years it was possible to look at local industries with greater statistical power than is possible using routine national statistics. Each case was matched with up to four controls of similar age who died in the same year from other causes. The occupations and industries recorded on death certificates were coded to standard classifications and risk estimates derived for each job category. Where positive associations were found the records of the cases concerned were examined in greater detail to see whether the risk was limited to specific combinations of occupation and industry. The most interesting findings to emerge were risks of brain cancer associated with the production of meat and fish products (relative risk (RR) = 9.7, 95% confidence interval (CI) 2.6-36.8) and with mineral oil refining (RR = 2.9, CI 1.2-7.0), and a cluster of four deaths from melanoma among refinery workers (RR = 16.0, CI CI 1.8-143.2). A job-exposure matrix was applied to the data but gave no strong indications of further disease associations. Local analyses of occupational mortality such as this can usefully supplement national statistics.

Adolescent↗