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Published on: June 20, 2020
Validation of the Functional Status II questionnaire in the assessment of extremely-low-birthweight infants
David Da Costa1, Carla M Bann, Nellie I Hansen
1Department of Pediatrics, William Beaumont Hospital, Royal Oak, MI, USA.
Insights
The revised Functional Status questionnaire (FS-II) effectively screens extremely low birthweight (ELBW) infants for functional impairments. This tool offers reliable measures of general health and independence, aiding in early identification of neurodevelopmental disabilities in ELBW survivors.
Area of Science:
- Neonatal research
- Developmental pediatrics
- Health outcomes assessment
Background:
- Increased survival rates of extremely low birthweight (ELBW) infants are linked to higher rates of neurodevelopmental disability.
- Formalized neurodevelopmental testing for ELBW infants is time-consuming and costly.
- The Functional Status questionnaire-II (FS-II) was developed to assess caregiver perceptions of functional status in chronically ill children.
Purpose of the Study:
- To evaluate the reliability and validity of the revised Functional Status questionnaire-II (FS-II) for assessing extremely low birthweight (ELBW) infants.
- To adapt and validate the FS-II for use in ELBW survivors aged 18-22 months corrected age.
- To establish appropriate screening scales for functional status in ELBW infants.
Main Methods:
- Utilized data from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network (NRN).
- Conducted exploratory factor analyses on data from 1080 children (1993-1994) and confirmed results with 4022 children (1995-2000).
- Assessed reliability using Cronbach's alpha and validity by comparing FS-II scores with the Bayley Scales of Infant Development-II (BSID-II) and medical conditions.
Main Results:
- A two-factor solution, comprising general health and independence, was identified as most appropriate for ELBW infants.
- The developed scales demonstrated good internal consistency (Cronbach's alpha=0.87 for general health, 0.75 for independence).
- Scores on the FS-II scales correlated significantly with BSID-II scores and medical conditions, supporting construct validity.
Conclusions:
- The adapted FS-II scales for general health and independence are valid and reliable for screening extremely low birthweight infants.
- Infants with poorer functional status (based on BSID-II or medical conditions) exhibited lower scores on the FS-II scales.
- These findings support the use of the FS-II as a practical tool for identifying functional impairments in ELBW survivors, facilitating timely interventions.
Aim:
The increased survival of infants born at extremely low birthweight (ELBW) has been associated with significant morbidity, including higher rates of neurodevelopmental disability. However, formalized testing to evaluate these problems is both time-consuming and costly. The revised Functional Status questionnaire (FS-II) was designed to assess caregivers' perceptions of the functional status of children with chronic diseases.
Method:
We evaluated the reliability and validity of the FS-II for ELBWinfants at 18 to 22 months corrected age using data from the US Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network (NRN). Exploratory factor analyses were conducted using data from the network's first follow-up study of 1080 children born in 1993 to 1994 (508 males, 572 females [53%]), and results were confirmed using data from the next network follow-up of 4022 children born in 1995 to 2000 (1864 males, 2158 females [54%]).
Results:
Results suggest that a two-factor solution comprising measures of general health and independence is most appropriate for ELBW infants. These factors differed from those found among chronically ill children, and new, more appropriate scales are presented for screening ELBWsurvivors. Both scales demonstrated good internal consistency: Cronbach's a=0.87 for general health and a=0.75 for independence. Construct validity of the scales was assessed by comparing mean scores on the scales according to scores on the Bayley Scales of Infant Development, second edition (BSID-II), and medical conditions.
Interpretation:
As hypothesized, infants with greater functional impairments according to their BSID-II scores or medical conditions had lower scores on the general health and independence scales, supporting the validity of the scales.
