Missing Data in a Long Food Frequency Questionnaire
نویسندگان
چکیده
منابع مشابه
The food frequency questionnaire.
To the Editors: Of course we agree with Kristal et al. (1) that validity is an issue of degree rather than a dichotomy and that multiple methods will usually be useful when evaluating validity because a perfect standard is rarely available. However, their examples based on face validity, construct validity, and predictive validity do not provide evidence that food frequency questionnaires shoul...
متن کاملDevelopment and Validation of a Food Frequency Questionnaire for Assessing Dietary Calcium in Children
Background and Objectives: This study aimed to develop and validate a food frequency questionnaire (FFQ) for measuring calcium intake in 9-13 years old children in Tehran, Iran. Materials and Methods: A 56-item FFQ containing main contributors of calcium in Iranian diet was designed. Criterion validity of the calcium specific FFQ was evaluated through comparing its result with five 24-h recall...
متن کاملMissing data imputation in multivariable time series data
Multivariate time series data are found in a variety of fields such as bioinformatics, biology, genetics, astronomy, geography and finance. Many time series datasets contain missing data. Multivariate time series missing data imputation is a challenging topic and needs to be carefully considered before learning or predicting time series. Frequent researches have been done on the use of diffe...
متن کاملValidation of a food-frequency questionnaire for use in pregnancy.
OBJECTIVES As a part of an ongoing project to develop a nutritional screening tool, we evaluated the performance of a semi-quantitative food-frequency questionnaire (FFQ) in terms of validity in a Sheffield Caucasian pregnant population using two different statistical approaches--the correlation coefficient and the limits of agreement (LOA). The FFQ was designed specifically for pregnant women ...
متن کاملAssessing long-chain ω-3 polyunsaturated fatty acids: a tailored food-frequency questionnaire is better.
OBJECTIVE Polyunsaturated fatty acids (PUFAs), including the long-chain (LC) ω-3 PUFAs, are important for health. The aim was to assess if the Anti-Cancer Council of Victoria Dietary Questionnaire (ACC DQ) accurately determines PUFA intakes compared with the recently validated electronic PUFA food-frequency questionnaire (FFQ). METHODS Forty-one study volunteers were recruited from the local ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Epidemiology
سال: 2009
ISSN: 1044-3983
DOI: 10.1097/ede.0b013e31819642c4