Unemployment and mortality in post-war Scotland

One of the more controversial topics in the literature examining the influence of unemployment on health is the hypothesised relation between unemployment and mortality. This paper presents a time series analysis of unemployment and mortality in post-war Scotland. Using a variety of model specifications and several measures of the age and duration structure of male unemployment, we find little evidence of a consistent association between unemployment and male mortality from all causes in different age cohorts. Unemployment, however, appeared to be more closely associated with variations in mortality rates and ischaemic heart disease, but the direction of effect was sensitive to the choice of maximum lag length between unemployment and mortality. There was also little evidence that per-capita real incomes or health expenditure exerted a significant influence on mortality. Our general findings and the methodological limitations of macro-studies of the relationship between unemployment and mortality highlight the importance of investigating the health consequences of unemployment using well controlled longitudinal studies of individuals.

A classification of Scottish infants using latent class analysis

This paper illustrates the use of latent class analysis to classify 50,000 infants into a small number of classes or case types, as a preliminary to a study of the allocation of neonatal hospital resources throughout Scotland. Information, extracted from a detailed neonatal discharge record, was summarized by 11 clinical and diagnostic catagorical variables. Statistical models incorporating 1 to 6 latent classes were then estimated using the EM algorithm. The 4 class model was chosen because it provided a good description of the data and the resulting classes had a medical interpretation. The factors influencing the choice of model are discussed and goodness of fit tests are presented. The stability of the classes was also investigated using random halves of the data and an earlier comparable data set.

A comparative analysis of birthweight for gestational age standards

The possible consequences of the use of various birthweight-for-gestational age standards in a local population were investigated. Birthweight-for-gestational age standards based on the analysis of 55 387 births occurring to women resident in the area of the Greater Glasgow Health Board (GGHB) between 1975 and 1979 were estimated. The Glasgow based standard was then compared with a number of growth standards reported for other populations, including the widely adopted standards of Thomson et al. (1968). The relative performance of each standard when applied to the Glasgow population was assessed by calculating the sensitivity, specificity and predictive value of the various standards vis-à-vis the distribution of light-for-dates infants defined according to the Glasgow standard. The results suggest that both the accurate assessment of fetal growth at birth and the evaluation of screening procedures for antenatal detection of growth retardation require growth standards reflecting the pattern of fetal growth and development in the population at risk.

Perinatal mortality in Scotland: 1970-9

An examination of the recent decline in perinatal mortality in Scotland during the 1970s showed that despite substantial changes in fertility and the demographic pattern of births, differences in the age, parity, and social class composition of the obstetric population in this decade accounted for just 7% of the overall improvement in perinatal mortality between 1970 and 1979. The general pattern of relative risks associated with maternal age, parity, and social class remained largely unchanged. Marginal changes in the birthweight distribution, however, were sufficient to account for 13% of the reduction in perinatal mortality. The low birthweight infant, especially those weighing under 1500 g, assumed increasing importance as a factor in perinatal mortality owing to a progressive worsening in the relative risk of perinatal mortality associated with low birth weight. Although regional differences in perinatal mortality persisted over this period, there occurred some lessening of the traditional inequality between western and eastern parts of the country. Finally, registered causes of perinatal mortality are reviewed. In the absence of other explanations the results of this analysis, collectively, suggest that much of the recent decline in perinatal mortality was perhaps due to changes in obstetric practice and in the clinical management of neonatal morbidity.

Multimodality treatment of cancer

Different and effective modalities are available for various cancers. However, early consideration is necessary to allow optimal integration. Failure to do this may compromise the cure potential for some tumours. The differing biology of tumours and the efficacy of various modalities dictates specific approaches for each. The principles of multimodality therapy can be considered together with the biological factors affecting the success and failure of each therapy tupe and this allows a multimodality approach to be based on careful planning. For many tumours, where effective systemic therapy exists, there are good reasons for commencing with a multimodality approach at the onset with adjuvant chemotherapy. Practical considerations dictate that surgeons must play a key role in the care of cancer patients. This in turn requires that they maintain a sound knowledge of multimodality therapy for the cancers that they treat.

Clinical trials symposium. Highlights in development of randomized clinical trials

The randomized clinical trial is accepted as the most reliable method of determining the relative merits of different therapies. At best it is a scientific experiment in the clinical setting, and demands all the rigors of experimental methods to produce valid data from which inference may be drawn. Randomization ensures the highest probability that the only difference between treated patient groups is the treatment given, and it is the component of clinical trials that produces the greatest ethical problems. It has three essential features. First, it eliminates investigator bias; second, it tends to balance known and unknown prognostic parameters in treatment groups; and, third, it forms the basis for the validity of statistical tests of significance.

Early breast cancer: part I: surgical pathology and preoperative assessment

The management of early breast cancer is showing a growing tendency to move away from radical surgery back towards conservative surgery and systemic adjuvant therapy. This paper and the one that follows review the data that underly this trend and consider the clinical and biological principles that are presently used to make a decision regarding the optimal primary treatment for breast cancer. The conclusion is reached that conservatism is based on a false understanding of the disease and on false conclusions drawn from premature analysis of data from clinical trials.

Optimal management can be determined by appropriate preparative investigation. Breast cancer patients can be divided into three groups: early cases, with a good prognosis, late, incurable cases and an intermediate group. Radical therapy by surgery or surgery combined with radiotherapy gives better results than a conservative approach in the early and intermediate groups. The intermediate group should be seen as having a poor, but not necessarily hopeless prognosis. These cases may benefit particularly from adjuvant chemotherapy, but this should not be used as an excuse to deny the patient adequate local measures, which alone (at present) offer hope of cure. The problem posed by the third group should be seen as one of optimal palliation.

Adjuvant systemic therapy raises hope of improving results, but no patient with breast cancer has yet been cured by chemotherapy or the application of immunological principles. Future improvements are most likely to derive from optimal use of each modality, and not at the expense of the most effective method at present available–radical surgery. The many remaining questions regarding management can best be answered by careful, controlled clinical studies, and every effort should be made to include patients with a poor prognosis in appropriate clinical trials.

The application of clinical trials to solid tumour management: an introduction

This paper discusses the relevance of clinical trials to the management of solid tumours. It introduces the types of clinical trials, the requirements for patient assessment, and an overall strategy for importance of statistical and ethical considerations is discussed. There is an invitation for practising surgeons to participate in trials relevant to their speciality. The necessay framework and requirements for a clinical protocol are discussed separately in the following paper.

Guidelines for planning clinical trials

This paper outlines the necessary steps involved in setting up and administering a clinical trial. The importance of adequate preparation, with careful definition of priorities and objectives, is emphasized. Guidelines for writing a clinical protocol are discussed in detail, as well as aids to deal with the running of the study, statistical planning, and presentation of results. The principle of different types of study, methods of patient assessment, and an overall plan of study, have already been introduced in the preceding paper.