Nutrition Commons^™

The Effectiveness Of A Short Food Frequency Questionnaire In Determining The Adequacy Of Vitamin D Intake In Children, Caitlin Russell

Caitlin S Russell

Background: Studies have consistently found a high prevalence of vitamin D deficiency in adolescents. Few validated dietary intake assessment tools for vitamin D exist for adolescents.

Objective: The aim of this study was to determine if a short food frequency questionnaire (SFFQ) can be used to effectively assess vitamin D intake in adolescents compared to a previously validated long food frequency questionnaire (LFFQ).

Participants/setting: 140 healthy 6-12 year old (male n=81) Caucasian and African American (n=94) children from Pittsburgh, Pennsylvania completed a SFFQ and LFFQ at two time points 6 months apart.

Main outcome measures: Reliability and validity of a …

An Introduction To Item Response Theory For Health Behavior Researchers, Russell Warne

Russell T Warne

OBJECTIVE:

To introduce item response theory (IRT) to health behavior researchers by contrasting it with classical test theory and providing an example of IRT in health behavior.

METHOD:

Demonstrate IRT by fitting the 2PL model to substance-use survey data from the Adolescent Health Risk Behavior questionnaire (n=1343 adolescents).

RESULTS:

An IRT 2PL model can produce viable substance use scores that differentiate different levels of substance use, resulting in improved precision and specificity at the respondent level.

CONCLUSION:

IRT is a viable option for health researchers who want to produce high-quality scores for unidimensional constructs. The results from our example-although not …