Methods of synthesizing qualitative research studies for health technology assessment

OBJECTIVES Synthesizing qualitative research is an important means of ensuring the needs, preferences, and experiences of patients are taken into account by service providers and policy makers, but the range of methods available can appear confusing. This study presents the methods for synthesizing qualitative research most used in health research to-date and, specifically those with a potential role in health technology assessment. METHODS To identify reviews conducted using the eight main methods for synthesizing qualitative studies, nine electronic databases were searched using key terms including meta-ethnography and synthesis. A summary table groups the identified reviews by their use of the eight methods, highlighting the methods used most generally and specifically in relation to health technology assessment topics. RESULTS Although there is debate about how best to identify and quality appraise qualitative research for synthesis, 107 reviews were identified using one of the eight main methods. Four methods (meta-ethnography, meta-study, meta-summary, and thematic synthesis) have been most widely used and have a role within health technology assessment. Meta-ethnography is the leading method for synthesizing qualitative health research. Thematic synthesis is also useful for integrating qualitative and quantitative findings. Four other methods (critical interpretive synthesis, grounded theory synthesis, meta-interpretation, and cross-case analysis) have been under-used in health research and their potential in health technology assessments is currently under-developed. CONCLUSIONS Synthesizing individual qualitative studies has becoming increasingly common in recent years. Although this is still an emerging research discipline such an approach is one means of promoting the patient-centeredness of health technology assessments

Young Netherlands Twin Register (Y-NTR): A longitudinal multiple informant study of problem behavior

summarizes the longitudinal genetic analyses of maternal and paternal ratings of twins ’ behavior as a function of the sex of the children for the traits of aggression (AGG), attention problems (AP), anxious/depression (ANX), internalizing behavior (INT) and externalizing behavior (EXT). We found that genetic influences are the most important factor in explaining individual differences in these traits. For most phenotypes, influences of genetic factors fluctuate throughout development, with the exception of AP, for which genetic influences remain of similar magnitude. Changes in genetic influences parallel those in shared environmental influences, while nonshared environmental influences remain relatively constant. Around 10 % to 20 % of the variance is accounted for by parent-specific shared environment, which includes rater bias. For all phenotypes, stability throughout childhood is accounted for by genetic and shared environmental factors, while nonshared environmental influences are mainly age/measurement specific. About 15 % of the phenotypic stability is accounted for by rater-specific shared environmental influences, which include rater bias. In conclusion, between ages 3 and 12 genetic factors are the most important cause of individual differences in emotional and behavioral problems. The Netherlands Twin Register (NTR) was established around 1987 at the Vrije Universiteit in Amsterdam, the Netherlands. Many twins and their families have been invited to participate since, in a wide variety of research projects. The twin register can be divided into two parts: (1) The Young Netherlands Twin Register (Y-NTR), which focuses on twins born after 1986 (and their family members)

The young Netherlands twin register (YNTR): Longitudinal twin and family studies in over 70,000 children

The Netherlands Twin Register (NTR) began in 1987 with data collection in twins and their families, including families with newborn twins and triplets. Twenty-five years later, the NTR has collected at least one survey for 70,784 children, born after 1985. For the majority of twins, longitudinal data collection has been done by age-specific surveys. Shortly after giving birth, mothers receive a first survey with items on pregnancy and birth. At age 2, a survey on growth and achievement of milestones is sent. At ages 3, 7, 9/10, and 12 parents and teachers receive a series of surveys that are targeted at the development of emotional and behavior problems. From age 14 years onward, adolescent twins and their siblings report on their behavior problems, health, and lifestyle. When the twins are 18 years and older, parents are also invited to take part in survey studies. In sub-groups of different ages, in-depth phenotyping was done for IQ, electroencephalography , MRI, growth, hormones, neuropsychological assessments, and cardiovascular measures. DNA and biological samples have also been collected and large numbers of twin pairs and parents have been genotyped for zygosity by either micro-satellites or sets of short nucleotide polymorphisms and repeat polymorphisms in candidate genes. Subject recruitment and data collection is still ongoing and the longitudinal database is growing. Data collection by record linkage in the Netherlands is beginning and we expect these combined longitudinal data to provide increased insights into the genetic etiology of development of mental and physical health in children and adolescents