The measurement properties of tests and tools used in cystic fibrosis studies: a systematic review

There is no consensus on how best to measure responses to interventions among children and adults with cystic fibrosis (CF). We have systematically reviewed and summarised the characteristics and measurement properties of tests and tools that have been used to capture outcomes in studies among people with CF, including their reliability, validity and responsiveness. This review is intended to guide researchers when selecting tests or tools for measuring treatment effects in CF trials. A consensus set of these tests and tools could improve consistency in how outcomes are captured and thereby facilitate comparisons and synthesis of evidence across studies.

Randomized clinical trial of behavioral and nutrition treatment to improve energy intake and growth in toddlers and preschoolers with cystic fibrosis

OBJECTIVE

To conduct a randomized clinical trial comparing a behavioral and nutrition intervention (BEH) with a usual care control condition (CTL) for children (ages 18 months to 4 years) with cystic fibrosis (CF) and pancreatic insufficiency. This trial was designed to (1) evaluate a randomized comparison of BEH with CTL over 8 weeks, (2) provide a replication of the impact of BEH by inviting the CTL group to receive BEH after 8 weeks, and (3) examine the maintenance of BEH at 3- and 12-month follow-up.

METHODS

Of 14 eligible children, 10 were randomly assigned and initiated treatment (71% recruitment rate). Four participants were randomly assigned to BEH, and 6 were assigned to CTL (5 of whom chose to crossover to BEH). BEH included nutrition counseling to increase energy intake (via types of foods and addables/spreadables) and child behavioral management training to teach parents differential attention and contingency management skills. CTL was consistent with the 2002 CF Foundation Consensus Conference Guidelines for nutritional care.

RESULTS

BEH led to greater increases in energy intake pre- to posttreatment than CTL as measured by calories per day (842 kcal/day vs -131 kcal/day change). On receiving BEH, the change in energy intake was replicated with the CTL group (892 kcal/day change). At 3- and 12-month follow-up, energy intake was maintained (672 kcal/day increase from baseline and 750 kcal/day increase from baseline, respectively). Children in this study met or exceeded normal weight and height velocities from pretreatment to the 3-month follow-up (mean weight: 1.4 kg/6 months; mean height: 5.1 cm/6 months) and from posttreatment to the 12-month follow-up (mean weight: 2.5 kg/12 months; mean height: 8.3 cm/12 months).

CONCLUSIONS

Toddlers and preschoolers who have CF and received BEH were able to meet the energy intake recommendations for this disease and maintain these gains up to 12 months after treatment. In addition, these children demonstrated weight and height velocities from pretreatment to 12-month follow-up, consistent with the goal of normal growth. BEH is a promising, evidence-based, early nutritional intervention for children with CF. An upcoming multisite clinical trial will test BEH versus an attention control condition using a larger sample (N = 100), providing additional evidence about the efficacy of this treatment for energy intake and growth in young children with CF.