Relative validity of dietary patterns during pregnancy assessed with a food frequency questionnaire

Abstract

This study aimed to assess the relative validity of maternal dietary patterns derived from a semi-quantitative food frequency questionnaire (FFQ). A total of 162 pregnant women aged 19–40-years-old were enrolled from the Universiti Sains Malaysia (USM) Birth Cohort Study in year 2010 and 2011. The FFQ was compared with three 24-h dietary recalls (DRs). Two major dietary patterns were derived from the principle component analysis which are labeled as Healthy and Less-Healthy patterns. The Pearson correlation coefficients between FFQ and DRs for Healthy and Less-Healthy patterns were 0.59 and 0.63, respectively. At least 45% of the participants were correctly classified into the same third from the FFQ and DR for both dietary patterns. The weighted kappa showed moderate agreement for Healthy pattern while good agreement for Less-Healthy pattern between these two dietary assessment methods. Our results indicate reasonable validity of the dietary patterns identified from the FFQ in pregnant women.     

Reproducibility and validity of a Chinese food frequency questionnaire used in Taiwan

A 64-item Chinese food frequency questionnaire (FFQ) combined with open questions on types of staples and cooking oil most frequently consumed was designed for a prospective study in Taiwan to appraise participants' usual intake. We examined its reproducibility and validity. The form was administered three times at three-month intervals by face-to-face interview to 83 senior college students majoring in nutrition, in order to recall their usual dietary intake over the past six months. They also completed five-day (includes both weekends) diet records (DR) after each interview. Averaged intake levels of most nutrients assessed by the three FFQs were slightly higher than those of 15-day DR. Intraclass correlation coefficients for nutrient intakes assessed by three FFQs three months apart ranged from 0.37 for saturated fat to 0.82 for alcohol (average: 0.52). Averaged Pearson correlation coefficients between the unadjusted and energy-adjusted nutrient intakes measured by DR and by the third FFQ (which asked about diet during the six months encompassing the diet records) were 0.40 and 0.35, respectively, not including vitamins A and C. These correlations were higher (average: 0.47) after adjusting for the daily variation of the diet records. On average, 50% subjects were correctly classified into the same tertiles by both methods; 11% of the subjects were misclassified to extreme categories. These data indicate that this FFQ for Chinese-speaking people in Taiwan is reproducible and provides a useful measure of intake for many nutrients over a six-month period.     

Reproducibility and validity of a food frequency questionnaire

OBJECTIVE: Methods to evaluate food consumption still need improvement. A study was conducted to verify the reproducibility and validity of a food frequency questionnaire (FFQ) among overweight adults. METHODS: The study was carried out in a private university in S?o Paulo, Brazil. The study sample consisted of 146 individuals of both sex with body mass index =25 kg/m2 and age between 18 and 60 years old. For reproducibility the FFQ was applied by trained interviewers at two different instances with a mean interval time of 47 days. For validity, data collected from the FFQ were compared with those obtained from the average of 3 different daily records of a 24-hour dietary recall (mean interval time: 15 days). Validity and reproducibility of data on calories and macronutrients consumption was assessed using pondered kappa statistics and intraclass correlation coefficient. RESULTS: A higher variability in the reporting of regular food consumption was seen among obese than overweight individuals. Concerning reproducibility, kappa statistical values varied from 0.23 (carbohydrates and fats) to 0.40 (calories), and intraclass correlation coefficients ranged from 0.28 (protein) to 0.54 (total calories). For FFQ validity, the highest kappa value was 0.25 (calories), and the intraclass correlation coefficient was 0.21 (protein). CONCLUSIONS: Food consumption reports of overweight individuals tend to be underestimated. Despite its limitations, FFQ could be used in epidemiological studies to assess the regular food consumption of overweight individuals.     

Reproducibility and validity of a semi-quantitative food frequency questionnaire

The reproducibility and relative validity of a semi-quantitative food frequency questionnaire (FFQ) were evaluated. Subjects were 72 (36 men and 36 women) residents of N island, Shimane Prefecture in Japan, aged 50-76 years. The questionnaire was administered twice at an interval of one week (FFQ1, FFQ2), and 7-day weighing diet records were collected during that period. This protocol was conducted in summer and winter. The mean intakes for 11 nutrients calculated from the FFQ1 and FFQ2 were similar and, those from the FFQ1 were smaller than those from the diet records for all but fat and vitamin C. Pearson correlation coefficients assessing reproducibility between nutrient intakes from FFQ1 and FFQ2 ranged from 0.59 for vitamin C to 0.90 for carbohydrate. Validity was measured by comparing nutrient intakes from FFQ1 with those from the 7-day diet record, and Pearson correlation coefficients ranged from 0.15 for iron to more than 0.35 for total energy and macronutrients. These correlation coefficients showed slight difference by gender or age group, but did not vary materially between seasons. These data indicate that this questionnaire is reproducible but has some problems in validity.     

Reproducibility and validity of major dietary patterns among Swedish women assessed with a food-frequency questionnaire

Defining dietary patterns by factor analysis is an alternative approach to dietary assessment that has been used recently to examine diet-disease relations. However, only 1 study evaluated the reproducibility and validity of this method. Our aim was to assess both the validity and reproducibility of major dietary patterns based on data from a 60-item FFQ. We chose 2 independent random samples among over 60,000 women aged 40-74 y participating in the Swedish Mammography Cohort (SMC). In the validation study, the FFQ was compared with 4 7-d dietary records (DRs) among 129 women. For the reproducibility study, the FFQ was administered twice, 1 y apart in 212 women. By conducting factor analysis, 3 major dietary patterns were identified: healthy (high in vegetables, fruits, fish, poultry, tomato, cereal, and low-fat dairy products), Western (processed meat, meat, refined grains, sweets, and fried potatoes), and drinker (beer, wine and liquor, snacks) pattern. These 3 patterns explained 29-34% of the total variance in these 2 studies. The Spearman correlation coefficients between FFQ1 and FFQ2 (reproducibility) for healthy, Western, and drinker pattern were 0.63, 0.68, and 0.73, respectively (all P < 0.0001). Correlation coefficients between the FFQ and DRs (validity) for these patterns were 0.59, 0.50, and 0.85, respectively (all P < 0.0001). Our results indicate that identification of dietary patterns through factor analysis is a reproducible and valid method. The dietary patterns approach might be used in nutritional epidemiology as an alternative method of dietary assessment.     

Reproducibility of a food frequency questionnaire: Korea Nurses' Health Study

BACKGROUND/OBJECTIVESThis study aimed to examine the reproducibility of food frequency questionnaires (FFQs) designed for young female nurses in the Korea Nurses'' Health Study.SUBJECTS/METHODSThe reproducibility of web-based, self-administered FFQs was evaluated among 243 Korean female nurses. The first FFQ (FFQ1) was administered from March 2014 to February 2019 and the second FFQ (FFQ2) from November 2019, with a mean interval of 2.8 years between the FFQs (range, 9 months–5.6 years). Pearson and Spearman correlation coefficients (r values) and quartile agreements between FFQ1 and FFQ2 were calculated for intakes of energy, nutrients, and foods.RESULTSPearson correlation coefficients ranged from 0.41 to 0.55 (median r = 0.51) for energy and raw nutrients and from 0.16 to 0.46 (median r = 0.36) for energy-adjusted nutrients. Spearman correlation coefficients ranged from 0.25 to 0.72 (median r = 0.41) for food items. The percentages of women who were classified into the same or adjacent quartile were 77% to 84% (median = 82%) for raw nutrients and 69% to 86% (median = 78%) for foods.CONCLUSIONSThe results indicated that the web-based FFQ used in the Korea Nurses'' Health Study has acceptable reproducibility.     

Reproducibility and validity of food intake measurements from a semiquantitative food frequency questionnaire

Few food frequency questionnaires have been evaluated for their ability to assess intakes of individual foods that may be related to disease independently of their nutrient content. The reproducibility and validity of food intake measurements by a 131-item semiquantitative food frequency questionnaire were evaluated in a sample of 127 men from the Health Professionals Follow-up Study, a large longitudinal study of diet and disease. Each subject completed two questionnaires 1 year apart and two 1-week diet records 6 months apart during the intervening year. Pearson correlations assessing reproducibility between food intakes from the two questionnaires ranged from .31 for pie to .92 for coffee (mean = .59). Validity was measured by comparing food intakes from the second questionnaire with those from the diet records. Pearson correlations corrected for within-person weekly variation in diet record data ranged from .17 for other nuts to .95 for bananas (mean = .63). Large within-person variation precluded the calculation of accurate validity correlations for 29 foods. As we previously observed in women, the foods most often overreported were fruits and vegetables, and meats and dairy products were most often underreported. With few exceptions, reasonable levels of reproducibility and validity were observed for intake of individual foods in this extensive food frequency questionnaire.     

Reproducibility and validity of dietary assessment instruments. II. A qualitative food frequency questionnaire

The reproducibility and validity of a food frequency questionnaire designed to measure intakes of total fat, saturated and polyunsaturated fats, vitamins A, C, and E, selenium, and dietary fiber were tested from March to October 1984 among 297 Finnish men aged 55-69 years. The questionnaire asked about consumption of 44 food items. In the reproducibility study, 107 subjects filled in the questionnaire three times, at three-month intervals. Intraclass correlations varied from 0.52 for vitamin A to 0.85 for polyunsaturated fat. In the validity study, 190 subjects kept food consumption records for 12 two-day periods distributed evenly over a period of six months and filled in the questionnaire both before and after this period. Correlations between the nutrient intake values from the food records and those from the food frequency questionnaires ranged from 0.33 for selenium to 0.68 for polyunsaturated fat. On the average, 40-45% of the subjects in the lowest and highest quintiles based on food records were in the same respective quintiles when assessed by the food frequency questionnaire, and 70-75% were in the two lowest and two highest questionnaire quintiles, respectively. The food frequency questionnaire and a quantitative food use questionnaire tested in the same study were compared. Use of these two instruments in large-scale epidemiologic studies is discussed.     

Relative validity of a food frequency questionnaire used to assess food intake during a dietary intervention study

To develop a cost-effective alternative for evaluating dietary intake in large-scale intervention trials of cancer and cardiovascular disease outcomes, we designed and validated a semiquantitative food frequency questionnaire (FFQ). We collected 6 to 8 of the 24-hr dietary recalls from 87 adults (ages 30-72 yr) who were randomly assigned to a walnut-supplemented diet or a control diet in a 6-mo dietary intervention trial. Relative validity of a 171-item FFQ in assessing intake of selected foods and the prescribed intervention (intake > or =25 g/day or intake < 2 g of walnuts) was determined using 24-h dietary recalls as the reference. De-attenuated correlations between FFQ and dietary recalls were .82 for walnuts, .80 for fruits, .79 for grains, .77 for vegetables, .63 for water, .44 for sweets, and .36 for dairy/eggs. High within-person variation did not allow de-attenuation for the remaining foods, but uncorrected correlations were high (> .7) for the beverage variables. The FFQ correctly classified 86 out of 87 subjects in the 2 prescribed intervention groups. The FFQ can provide an accurate measure of a food-based intervention (i.e., walnut supplementation) in a trial setting and can also accurately estimate a number of other food groups consumed during the trial.     

Reproducibility and validity of semi-quantitative food frequency questionnaire measuring dietary trans-fatty acids intake among Korean adults

BACKGROUND/OBJECTIVESCompelling evidence indicates that consumption of trans-fatty acids (TFA) is associated with a wide range of diseases. However, few validated tools for TFA intake assessment are available in Korea. We aimed to validate a food frequency questionnaire (FFQ) estimating usual intake of TFA in Korean adults.MATERIALS/METHODSEighty-two healthy adults completed an FFQ with a 3-day diet record (3DDR), and 58 completed a second FFQ at a 1-month interval. To assess the reproducibility of the FFQ, we compared estimated TFA intakes from each FFQ. To assess the validity, we compared estimates from the FFQ with those from the 3DDR.RESULTSThe FFQ was reproducible (Spearman r = 0.71) and provided modest correlations with the 3DDR (Spearman r = 0.38). After adjustment for total energy intake, the correlations increased (r = 0.45). Measurement-error correction also de-attenuated the correlations (r = 0.57). When quintiles of the FFQ and 3DDR were joint-classified, 9% on average were misclassified into extreme quintiles.CONCLUSIONSOur findings suggest that the developed FFQ is reproducible and reasonably valid in categorizing individuals according to TFA intakes among healthy young and middle aged adults in Korea.     

Reproducibility and validity of a food frequency questionnaire in European and polynesian New Zealanders

The reproducibility and validity of a self‐administered 142‐item food‐frequency questionnaire (FFQ) was assessed in a population comprising 124 European and 52 Polynesian (17 Maori and 35 Pacific Island) New Zealanders aged 40–65 years. Reproducibility correlation coefficients, determined by administration of the same questionnaire on two occasions 3 years apart, were higher in European than Maori and Pacific Island. participants, ranging from 0.47 to 0.87 in Europeans (median 0.66) and from 0.41 to 0.79 in Maori and Pacific Island people (median 0.44). In general, there were no significant differences in mean nutrient intakes calculated from the two FFQs by Europeans or Maori and Pacific Island participants despite their cultural and language differences. When the FFQ was compared with a 3‐day food diary in a sub sample of 101 Europeans, 15 Maori and 22 Pacific Islanders, the validity was good for most nutrients, with overestimation of a few nutrients in each ethnic group. Correlation coefficients between the 3‐day food diary and FFQ ranged from 0.41 to 0.81 in Europeans (median 0.48) and from 0.36 to 0.56 in Maori and Pacific Island people (median 0.55). Ratios of energy intake to resting metabolic rate suggested that Maori and Pacific Island people were more likely to underestimate their habitual energy intake by the 3‐day diet diary method compared to Europeans, but that Europeans were more likely to underestimate total energy intake by the food frequency method and Pacific Island participants to overestimate it. Obese Europeans and Maori were more likely to under‐report dietary intakes by the 3‐day diary method. We conclude that our FFQ performed better in European than Maori and Pacific Island participants.     

Reproducibility and validity of a simple checklist-type questionnaire for food intake and dietary behavior

BACKGROUND: A simple, reliable, and valid food questionnaire is needed in clinical dietary assessments, community health education, and multi-purpose epidemiologic studies to obtain a crude measure of dietary intake. METHODS: To assess the validity and reproducibility of a simple 4-point scale food intake and behavior checklist, it was compared to two 3-day weighed dietary records. The FBC was administered to 47 students of a dietician course and their parents (n = 94) over a 9-month interval to assess the reproducibility. The mean intakes of selected food groups assessed by the two dietary records completed between food intake and behavior checklists were compared to the responses to the food intake and behavior checklist to assess its validity. RESULTS: The kappa statistics for reproducibility ranged from 0.25 for confectionaries to 0.63 for a preference for fatty foods (median, 0.39). There was a reasonable level of correlation between the dietary record and the food intake and behavior checklist in the intake of eggs, milk, and fruits (r = 0.53, 0.56, and 0.50, respectively). There was a weaker but still significant correlation in the intake of vegetables, and alcohol (r = 0.31 and 0.45, respectively). No significant correlation was observed in the intake of meat, fish, confectionaries, and soft drinks. However, those who reported consuming mainly fish rather than meat were found to eat significantly less meat and animal fat. Similarly, those who did not prefer fatty foods consumed significantly less meat, animal fat, and polyunsaturated fatty acids. CONCLUSIONS: This simple food checklist was useful in collecting data on egg, milk, and fruit consumption. Assessing intake frequency of vegetables, meat or fish with the FBC may be useful in screening high- or low-intake individuals.     

Reproducibility and comparative validity of a food frequency questionnaire for Australian children and adolescents

Background  

Dietary intake during childhood and adolescence is of increasing interest due to its influence on adult health, particularly obesity, cardiovascular disease and diabetes. There is a need to develop and validate dietary assessment methods suitable for large epidemiologic studies of children and adolescents. Limited large scale dietary studies of youth have been undertaken in Australia, due partly to the lack of a suitable dietary intake tool. A self-administered, semi-quantitative food-frequency questionnaire (FFQ), the 'Australian Child and Adolescent Eating Survey' (ACAES), was developed for youth aged 9-16 years. This study evaluated reproducibility and comparative validity of the ACAES FFQ using assisted food records (FRs) as the reference method.     

北京市儿童青少年食物频率问卷的信度和效度研究

目的 对研制的北京市儿童青少年食物频率问卷的信度和效度进行评价,为儿童青少年营养状况评估和健康干预以及饮食习惯与慢性疾病关联性的研究提供一个简便、可信的研究工具。方法 对北京市130名10~17岁儿童青少年进行4次24 h饮食回顾调查和2次食物频率问卷调查,24- h饮食回顾作为“标准”方法与食物频率问卷比较来评价其效度, 2次间隔6个月的食物频率问卷调查结果相比较来评价其信度。结果 两次食物频率问卷调查结果间能量及营养素摄入量估计差异较小,除蛋白质、磷和锌的摄入量第二次低于第一次外(P<0.05),其他营养素摄入量间差异无统计学意义(P>0.05)。两次食物频率问卷调查结果间所有能量及营养素摄入量均呈正相关(P<0.01),Pearson相关系数从0.315(钙)至0.521(锌),平均为0.431,女性高于男性(0.49 vs 0.32)。食物频率问卷调查的能量及营养素摄入量均高于24 h饮食回顾(P<0.01),食物频率问卷高估明显。调整总能量摄入和个体内变异等影响后,食物频率问卷与24 h饮食回顾调查结果的能量和所有营养素摄入量均呈正相关(P<0.05),Pearson相关系数从0.27(维生素A)至0.53(锌),平均0.38。四分位分组显示:研究对象被良好区分(相同组或相邻组),比例从66.2%(维生素E、钙)至79.2%(铁),平均73.0%,研究对象被严重错分(相隔2组),比例平均为6.2%。结论 此食物频率问卷有较好的信度和效度,可作为今后儿童青少年膳食营养摄入状况调查和评价的适用工具。     

Reproducibility and accuracy of a food frequency questionnaire used for diet intervention studies

The purpose of the present investigation was to determine whether altering the format of a food frequency questionnaire affected its accuracy and reproducibility. Three questionnaires were tested at one-month intervals. Questionnaire I contained 39 food items listed according to food categories. Questionnaire II contained 55 food items, presented according to the meal in which they were consumed. Questionnaire III contained 31 food items presented in a similar order to that in Questionnaire II. To determine the accuracy of the food frequency questionnaire, results were compared to those obtained from a simultaneously administered seven-day diet diary. Results from this study showed that food frequency questionnaires containing broad categories of food items presented in order of the meals in which they are consumed are the most reproducible. Highly reproducible results also can be obtained from seven-day diet diary, if data are calculated in terms of nutrients (i.e. carbohydrates, fats, proteins, etc.) and not specific food items. Finally, this study suggests that individuals more closely maintain their intake of nutrients, rather than specific food items.     

Relative validity of a food frequency questionnaire used in the Inter99 study

Objective:To evaluate the validity of the Inter99 food frequency questionnaire (FFQ) compared with a 28-days' diet history and biomarkers.Subjects:A random sample of 13 016 individuals were drawn from a general population and invited for a health screening programme. Participation rate was 52.5%. All high-risk individuals were re-invited for assessment after 1 and 3 years and completed a 198-item FFQ at all three occasions. Participants attending for 3 years follow-up were invited to participate in the validation study, including a 28-days' diet history, a 24-h urine collection and a fasting blood sample. Overall, 264 subjects participated.Results:Spearman's rank correlation coefficients between the two dietary methods ranged from 0.31(beta-carotene) to 0.64 (fruits) in men and from 0.31 (polyunsaturated fat and sodium) to 0.64 (fruits) for women. The proportion of individuals classified in the same or adjacent quintiles were, on average, 72% for men and 69% for women. Gross misclassification was found on average in 2%. The correlation coefficients of the residuals ranged from 0.27 (sodium) to 0.61 (fruits) for men and from 0.21 (sodium) to 0.62 (B12-vitamin) for women. Correlation coefficients between fruit and vegetable intake and carotenoids ranged from -0.08 (lycopene) to 0.44 (alpha-carotene). For the residuals the correlation coefficients ranged from -0.004 (lycopene) to 0.47 (alpha-carotene).Conclusion:The Inter99 FFQ and the residuals of the intake provide acceptable classification of individuals according to their dietary intakes and the FFQ gives a good quantitative measurement of key dietary components.European Journal of Clinical Nutrition (2008) 62, 1038-1046; doi:10.1038/sj.ejcn.1602815; published online 30 May 2007.     

Reproducibility and relative validity of food group intake in a food frequency questionnaire developed for Nepalese diet

We developed a food frequency questionnaire (FFQ) designed to measure the dietary practices of adult Nepalese. The present study examined the validity and reproducibility of the FFQ. To evaluate the reproducibility of the FFQ, 116 subjects completed two 115-item FFQ across a four-month interval. Six 24-h dietary recalls were collected (1 each month) to assess the validity of the FFQ. Seven major food groups and 23 subgroups were clustered from the FFQ based on macronutrient composition. Spearman correlation coefficients evaluating reproducibility for all food groups were greater than 0.5, with the exceptions of oil. The correlations varied from 0.41 (oil) to 0.81 (vegetables). All crude spearman coefficients for validity were greater than 0.5 except for dairy products, pizzas/pastas and sausage/burgers. The FFQ was found to be reliable and valid for ranking the intake of food groups for Nepalese dietary intake.