Creation of a specific instrument to evaluate health-related quality of life in children with Down syndrome. First phase

Down syndrome (DS) is a genetic disorder characterized by the total or partial tripling of chromosome 21, which causes mental and growth retardation, physical disorders, and is associated with cardiovascular, orthopedic and metabolic comorbidities. According to the World Health Organization (WHO), the incidence is approximately 1 in every 1000 live births(1), where 70%-75% of people with DS have an IQ between 25 and 50, this being the most common cause of Intellectual Disability (ID)(2).

In Colombia, there are no figures on the burden of DS. Some estimates, such as those derived from the (3,4)Registry for the Location and Characterization of the Population with Disabilities(5), report an incidence of 17.2 children with DS for every 10,000 births. Ramirez et al(6) in a study conducted in 1996, reported an incidence in Cali of 1.5 per 1000 births. Finally, the 2005 census, which characterized the population with disabilities in Colombia by age, reported that 33% of people with some type of disability were children between the ages of 5 and 14(7).

Children with DS require health interventions that aim to improve their mental function, adaptive behavior and motor function, in such a way that these interventions improve their participation and interaction with others, thus improving performance in their social roles(8).

Throughout the life cycle, people with DS require a large number of interventions that ultimately seek to impact quality of life, which is why Health-Related Quality of Life (HRQL) should be one of the most important outcomes for evaluating the effectiveness of therapeutic interventions on children with DS and their families(4,9). Despite the importance of HRQOL in populations with chronic conditions such as DS, it is striking that HRQOL is not a commonly reported outcome in studies evaluating interventions in this population.

This may be the result of two main factors: on the one hand, measuring quality of life is not easy and requires more time from researchers, and on the other hand, there is no instrument that has been validated for measuring HRQOL in children with DS. This means that the items contained within the dimensions that have the same name are not comparable or correlated and finally, it is not certain whether these existing generic instruments represent a construct of HRQOL in children with DS. It is therefore necessary to identify suitable approaches for assessing HRQOL in children with DS in order to inform the impact of health interventions on this outcome, which is essential for decision-making in clinical practice (4,9).

Having an instrument that allows for the appropriate measurement of quality of life will also serve to develop cost-utility studies of health interventions in this population, a necessary input for evaluating the budgetary impact of specific intervention programs on this group of people who also make so many mistakes in this area of knowledge, which could also be another line of development in research for the Universidad del Rosario if initiatives like this one are supported.

The panorama described above shows great shortcomings in the health care provided to children with DS in the country, as the impact on the quality of life derived from the health interventions provided to these children is not known. It is therefore necessary to define the dimensions and attributes that make up the HRQOL construct in children with DS and thus be able to generate a specific instrument to evaluate the effect of therapeutic interventions on HRQOL in this population. This instrument requires the validation process to be carried out by determining its psychometric properties, internal consistency and test-retest reliability, in addition to the validation of the construct.

This proposal is the first phase of an initiative that aims to generate and evaluate the psychometric properties of a quality-of-life instrument for children with DS that will enable them to be included in the health care processes of this population at the national and international levels. This initiative has three phases 1) creation of the instrument, 2) national evaluation of psychometric properties: construct validity and reliability 3) international evaluation of construct validity and reliability (reproducibility, internal consistency and level of agreement).

This first phase of the project is aligned with the strategic interests of the School of Medicine and Health Sciences in the research ecosystem, since it will provide an instrument that makes it possible to measure the impact on the quality of life of interventions generated from research in the areas of genetics and pharmacology, mainly, whose authors have raised the need for specific instruments(10). This project represents a continuation of a line of work by its researchers in the creation of evaluation instruments for the diagnosis and effectiveness of therapeutic strategies in the clinical research line that belongs to the Rehabilitation Sciences Research Group. The developing group has successful experience in the generation of instruments, which makes it ideal for achieving the proposed objectives and expected impacts(11). The development of this project is part of the research improvement plan generated by the national and international accreditation process of the Physiotherapy program, as it provides an instrument that allows the effectiveness of health interventions aimed at improving the quality of life of children with DS to be measured.

The generation of the CVRS-SD instrument includes qualitative and quantitative methodological approaches that are expected to be achieved with the execution of seed capital resources.

The creation of the CVRS-SD starts from the definition of the construct that will be carried out through a review of the scientific literature, focus group strategy and Delphi method.

The focus group strategy will be carried out with adults with DS, parents of children with DS and caregivers, in order to obtain information that can contribute to the validity of the content. Expert consensus following the Delphi method will validate the items generated with the two previous strategies.

The validity of appearance, in this study, will be conceived as the interpretation made in this case by the population reporting the instrument (adults with DS with the ability to follow instructions and nod), in addition, the parents and carers of children with DS will be investigated.