Table 2

Minimum meaningful differences between control and intervention groups, and those detectable with 80% power, 5% significance (two-tailed) for endpoint sample size of 265 per group, assuming a design effect of 2.9.

Intake

Prevalence #

Detectable

Behaviour

Prevalence #

Detectable


Fruita

82 vs ≥ 95%(iii)

82 vs ≥ 95%

Offer new food >10 timesb

28 vs ≥ 75%(iii)

28 vs ≥ 48%


Vegetablea

67 vs ≥ 95%(iii)

67 vs ≥ 84%

Refuses food- assume not hungry, take food away often/very often/alwaysb

56 vs ≥ 84%(i)

56 vs ≥ 75%


Salty snacksa

27 vs ≤ 17%(ii)

27 vs ≤ 11%

Refuses food-offers no replacement food often/very often/alwaysb

29 vs ≥ 44%(i)

29 vs ≥ 49%


Sweet beveragesa

44 vs ≤ 28%(ii)

44 vs ≤ 25%

Use food as reward 'hardly ever'b

55 vs ≥ 83%(i)

55 vs ≥ 74%


Fried potatob

17 vs ≤ 8%(i)

17 vs ≤ 5%

Insist child eat 'hardly ever'b

46 vs ≥ 69%(i)

46 vs ≥ 66%


# Prevalence = proportion of children consuming food on day of record - Anticipated and a priori defined meaningful differences in control versus active groups; Control prevalences are based on descriptive cross-sectional data from (a) FITS[14] or (b) our pilot study for infants 19-24 or 12-36 months respectively. Criteria to estimate expected differences (in direction of desirable intake/behaviour) were (i) relative increase/decrease of 50% (ii) equivalent to intake at 9-12 months or (iii) increase/decrease to optimal.

Daniels et al. BMC Public Health 2009 9:387   doi:10.1186/1471-2458-9-387

Open Data