Number Of Treatment Periods Research Articles

The development of a set of key points to aid clinicians and researchers in designing and conducting n-of-1 trials

Introductionn-of-1 trials are undertaken to optimise the evaluation of health technologies in individual patients. They involve a single patient receiving treatments, both interventional and control, consecutively over set periods of time, the order of which is decided at random. Although n-of-1 trials are undertaken in medical research it could be argued they have the utility to be undertaken more frequently. We undertook the National Institute for Health Research (NIHR) commissioned DIAMOND (Development of generalisable methodology for n-of-1 trials delivery for very low volume treatments) project to develop key points to assist clinicians and researchers in designing and conducting n-of-1 trials.MethodsThe key points were developed by undertaking a stakeholder workshop, followed by a discussion within the study team and then a stakeholder dissemination and feedback event. The stakeholder workshop sought to gain the perspectives of a variety of stakeholders (including clinicians, researchers and patient representatives) on the design and use of n-of-1 trials. A discussion between the study team was held to reflect on the workshop and draft the key points. Lastly, the stakeholders from the workshop were invited to a dissemination and feedback session where the proposed key points were presented and their feedback gained.ResultsA set of 22 key points were developed based on the insights from the workshop and subsequent discussions. They provide guidance on when an n-of-1 trial might be a viable or appropriate study design and discuss key decisions involved in the design of n-of-1 trials, including determining an appropriate number of treatment periods and cycles, the choice of comparator, recommended approaches to randomisation and blinding, the use of washout periods and approaches to analysis.ConclusionsThe key points developed in the project will support clinical researchers to understand key considerations when designing n-of-1 trials. It is hoped they will support the wider implementation of the study design.

Effect of Age and Number of Treatment Periods on Readiness to Quit Drinking

Effect of Age and Number of Treatment Periods on Readiness to Quit Drinking

Using re-randomisation to improve patient recruitment and increase statistical power in clinical trials

Patient recruitment is a major challenge for randomised trials. Reviews of publicly funded UK trials have found that 45 to 69% fail to recruit to target. This increases costs, delays results, and adversely impacts on the feasibility of conducting trials for conditions where there is a limited patient pool. For some conditions a patient requires treatment on multiple occasions. For example, patients with sickle cell disease require pain relief for each pain crisis, or women having fertility treatment undergo multiple treatment cycles until becoming pregnant. The current norm is for patients to be included for only one treatment episode. We propose a re-randomisation design, allowing patients to be randomised on multiple occasions, which could substantially increase the recruitment rate. We describe some properties of the re-randomisation design, such as the conditions required to obtain unbiased estimates of the treatment effect and control type I error rates, and offer advice on practical design and analysis issues. We show that this design can reduce the required number of patients compared with a parallel group design. It can be used in a wider variety of settings than a crossover design and may be more patient-centred as the number of treatment periods is determined by participants rather than the trial design. We also highlight situations where this design would be inappropriate.

Has the attempt to reduce psychiatric inpatient treatment been successful in Finland?

The deinstitutionalisation process in Finland’s psychiatric healthcare did not start until the late 1980s. Our aim is to evaluate how the use of psychiatric inpatient treatment was associated with deinstitutionalisation given the changes in the modality of treatment ideology (years 1987–1991) as well as being due to economic pressures (years 1991–1995). Special emphasis is given on the inpatient treatment of schizophrenia and other psychotic disorders. Data was retrieved using the national hospital discharge register of all treatment periods in psychiatric hospitals and treatment periods due to psychiatric disorders in other hospitals. Three years (1987, 1991, and 1995) were compared. Four healthcare districts in northern Finland were studied. Resource use was measured by number of treatment periods and inpatient days in relation to population. Psychiatric inpatient treatment was reduced in 1987–1991, when resources in community care increased. During the period of economic pressures (1991–1995), when community care resources no longer increased, inpatient treatment started to rise again. Over the whole period, psychiatric treatment in primary care institutions increased. Reduction of psychiatric beds results in increasing inpatient treatment in non-specialist institutions, especially when community care fails to serve the patients. In the future it is important to evaluate whether the quality of care remains in the standard of specialised services when treatment shifts away from the specialist level.

Single fibre electromyography in multifocal motor neuropathy with persistent conduction blocks

OBJECTIVETo study the process of denervation-reinnervation in multifocal motor neuropathy with persistent conduction blocks in clinically affected and unaffected muscles.METHODVolitional single fibre electromyography (SFEMG) was performed in the extensor digitorum...

Asthma related hospital treatment in Finland: 1972-86.

The number of asthma related treatment periods in hospital has increased in many countries, particularly among children. The aim of the present investigation was to describe the use made of hospital services by asthmatic patients over a wide range in Finland. A total of 255,387 treatment periods for asthma that had occurred between 1972 and 1986 was collected from the discharge register maintained by the National Board of Health (diagnosis 493, International Classification of Diseases). The numbers of admissions, days in hospital, and new occurrences of asthma were calculated by sex and age in relation to the total population at the end of each year. Asthma induced treatment periods in hospital in Finland were 12,860 (277 treatment periods per 100,000 inhabitants) in 1972 and 20,000 (406 per 100,000 inhabitants) in 1986. The annual increase in the number of such periods was 4.7% for men (95% confidence interval (95% CI) 3.5 to 5.9%) and 3.4% for women (2.1 to 4.7%) in relation to population. The most pronounced change was found in those aged 65 years and over, in which the number of treatment periods was found to increase annually by 7.5% (6.0 to 9.0%) for men and 4.9% (3.4 to 6.5%) for women, whereas the smallest increase was found among persons under 15 years with an annual change of 1.3% (0.2 to 2.3%) for boys and 1.1% (-0.1 to 2.4%) for girls. Although the number of asthma related treatment periods increased, that of new patients with asthma did not. An average of 114 new male asthmatic patients per 100,000 men were treated in hospitals annually between 1977 and 1986, whereas the figure for women was 115; the annual change during this 10 year period was 0.2% (-0.8 to 1.2%) for men and -0.8% (-1.8 to 0.2%) for women. The increase in the number of asthma related hospital treatment periods seemed attributable to the frequent treatment of the same patients. Treatment periods for persons aged 40 years or over were found to increase most, suggesting that the treatment of these asthmatic patients should be optimised and its organisation improved.

Statistical Power in Single Subject Trials

A controlled single subject trial compares the efficacy of a new treatment with a control treatment in an individual patient. The treatments are administered in a double-blind, randomized, multi-crossover sequence of periods. During the trial response measures are obtained from each treatment period and form the basis for the statistical evaluation. Similar to the situation in clinical trials using groups of patients the statistical power is dependent on sample size, variability of responses, magnitude of the differential treatment effect and the level of statistical significance. In addition, the randomization procedure is of importance and power estimations show that a pairwise random allocation of treatment periods is more powerful than an unrestricted randomization. Since a single subject trial is a time consuming approach, the total number of treatment periods, the sample size, is restricted in order to make such trials feasible. Accordingly, less rigorous statistical requirements and power must be accepted. The consequence is an increased risk of both Type I and II errors. However, in comparison with the trial and error approach frequently applied in clinical practice, the controlled single subject trial may improve the certainty of therapeutic decisions in the individual patient.

Attendance pattern and continuity of dental care of Finnish adults over a 5 year period.

The study deals with the frequency of using dental services and continuity of visting the same dentist by adults in Finland during the 5 years up to 1981. A representative sample of 17-65 year old Finnish adults was interviewed by telephone or when this was not possible, personally. The data were collected by the Central Statistical Office of Finland in autumn 1981. Twenty-two per cent of the subjects had not visited a dentist during the past 5 years. One-third had had more than three treatment courses during the same period. The number of treatment periods increased with higher educational and professional status. Half of the subjects who had had more than one treatment period had continued to attend the same dentist during different treatment periods. Young persons had changed dentist more often than older ones. The most common reason for changing dentist was change of residence. Nine percent did not wish to continue treatment with the same dentist. Income, age, profession and region of living accounted for 10% of the number of changes of dentist.