Beth Mittl

Cognitive research enhances accuracy of food frequency questionnaire reports: results of an experimental validation study

OBJECTIVE To test whether changing a food frequency questionnaire (FFQ) on the basis of cognitive theory and testing results in greater accuracy. Accuracy was examined for 4 design issues: a) Grouping: asking about foods in a single vs multiple separate questions; b) different forms of a food: asking consumption frequency of each form of a food (eg, skim, 2%, whole milk) vs a nesting approach--asking frequency of the main food (eg, milk) and proportion of times each form was consumed; c) additions (eg, sugar to coffee): asking independent of the main food vs nested under the main foods; d) units: asking frequency and portion size vs frequency of units (eg, cups of coffee). DESIGN Participants in two randomly assigned groups completed 30 consecutive daily food reports (DFRs), followed by 1 of 2 FFQs that asked about foods consumed in the past month. One was a new, cognitively-based National Cancer Institute (NCI) Diet History Questionnaire; the other was the 1992 NCI-Block Health Habits and History Questionnaire. SUBJECTS/SETTING 623 participants, age range 25 to 70 years, from metropolitan Washington, DC. Statistical analyses performed Accuracy was assessed by comparing DFR and FFQ responses using categorical (percent agreement) and continuous (rank order correlation, discrepancy scores) agreement statistics. RESULTS Grouping: accuracy was greater using separate questions. Different forms of food: accuracy was greater using nesting. Additions: neither approach was consistently superior; accuracy of the addition report was affected by accuracy of the main food report. Units: both approaches were similarly accurate. CONCLUSIONS Accuracy of FFQ reporting can be improved by restructuring questions based on cognitive theory and testing.

The Automated Self-Administered 24-Hour Dietary Recall (ASA24): A Resource for Researchers, Clinicians, and Educators from the National Cancer Institute

Extensive evidence has demonstrated that 24-hour dietary recalls (24HDRs) provide high-quality dietary intake data with minimal bias, making them the preferred tool for monitoring the diets of populations and, increasingly, for studying diet and disease associations (1-3). Traditional 24HDRs, however, are expensive and impractical for large-scale research because they rely on trained interviewers, and multiple administrations are needed to estimate usual intakes. To address these challenges, the National Cancer Institute (NCI), in collaboration with the research firm Westat (Rockville, MD), and with the support of other institutes and offices at the National Institutes of Health, developed the Automated Self-Administered 24-hour dietary recall (ASA24) (4-6). ASA24 is a public-access, freely available, web-based tool for researchers, clinicians and educators, modeled on the Automated Multiple Pass Method (AMPM) (7). Development of an automated self-administered 24HDR for adults began in 2006 and was informed by input from stakeholders participating in an External Working Group and small-scale cognitive and usability testing (4,5). A Beta version released in August 2009 has been used by over 175 researchers to collect over 40,000 recalls; Version 1, which offers improved usability and new features, was released in September 2011 (8). A modified version intended for self-administration by children is under development by researchers at the Baylor College of Medicine (Houston, TX) and is expected to be available mid-2012 (9,10). This paper describes the features of ASA24 and planned evaluations.

Assessment of the Accuracy of Portion Size Reports Using Computer-Based Food Photographs Aids in the Development of an Automated Self-Administered 24-Hour Recall

OBJECTIVE To assess the accuracy of portion-size estimates and participant preferences using various presentations of digital images. DESIGN Two observational feeding studies were conducted. In both, each participant selected and consumed foods for breakfast and lunch, buffet style, serving themselves portions of nine foods representing five forms (eg, amorphous, pieces). Serving containers were weighed unobtrusively before and after selection as was plate waste. The next day, participants used a computer software program to select photographs representing portion sizes of foods consumed the previous day. Preference information was also collected. In Study 1 (n=29), participants were presented with four different types of images (aerial photographs, angled photographs, images of mounds, and household measures) and two types of screen presentations (simultaneous images vs an empty plate that filled with images of food portions when clicked). In Study 2 (n=20), images were presented in two ways that varied by size (large vs small) and number (4 vs 8). SUBJECTS/SETTING Convenience sample of volunteers of varying background in an office setting. STATISTICAL ANALYSES PERFORMED Repeated-measures analysis of variance of absolute differences between actual and reported portions sizes by presentation methods. RESULTS Accuracy results were largely not statistically significant, indicating that no one image type was most accurate. Accuracy results indicated the use of eight vs four images was more accurate. Strong participant preferences supported presenting simultaneous vs sequential images. CONCLUSIONS These findings support the use of aerial photographs in the automated self-administered 24-hour recall. For some food forms, images of mounds or household measures are as accurate as images of food and, therefore, are a cost-effective alternative to photographs of foods.

Relative Validity of a Food Frequency Questionnaire with a Meat-Cooking and Heterocyclic Amine Module

The nutrient and heterocyclic amine (HCA) intake of 165 healthy participants was assessed using a self-administered food frequency questionnaire (FFQ), which included a meat-cooking practices module. A database containing the HCA [2-amino-3,8-dimethylimadazo [4,5-f] quinoxaline (MeIQx) and 2-amino-1-methyl-6-phenylimadazo [4,5-b] pyridine (PhIP)] composition of various types of meat, cooked by different methods and to varying degrees, was developed and validated in conjunction with this module. The relative validity of dietary and HCA intake estimated by the FFQ was investigated using multiple food diaries (3 sets of 4 nonconsecutive day diaries completed over a 3-month period) as the reference method. Crude correlation coefficients of HCA intake assessed by the FFQ and food diaries were 0.43 [95% confidence interval (CI) 0.30–0.55] for MeIQx and 0.22 (95% CI 0.07–0.36) for PhIP intake. Deattenuated correlations were 0.60 (95% CI 0.49–0.69) and 0.36 (95% CI 0.22–0.49), respectively. Absolute MeIQx and PhIP intake was, however, underestimated by the FFQ (21.9 and 78.1 ng/day) compared with the food diaries (34.9 and 263.8 ng/day). The FFQ underestimated total red meat intake, the percentage of consumers, and the median intake of roast/baked and microwaved red meat. PhIP intake was severely underestimated by the FFQ and was most likely because of an underestimation of the percentage of people who cooked chicken using PhIP-producing cooking methods such as broiling and pan-frying. Additionally, the FFQ overestimated the percentage of consumers of baked chicken, a cooking method that produces less PhIP. In conclusion, although the FFQ and meat module underestimated absolute MeIQx and PhIP intake, its ability to rank individuals according to intake was acceptable.

Comparison of the 60- and 100-Item NCI-Block Questionnaires With Validation Data

Large epidemiological studies often require short food frequency questionnaires (FFQ) to minimize the respondent burden or to control for confounding from dietary factors. In this analysis, we compared the extensively used National Cancer Institute-Block 60- and 100-item FFQs with one another and with usual intake as estimated from 12 days of validation data. The analysis focused on nutrients from different aspects of the diet, including energy, fat, saturated fat, beta-carotene, dietary fiber, and vitamin C. By use of an errors-in-variables analysis, the correlations of usual intake with the two types of FFQs for these nutrients were not different. Attenuation coefficients, a measure of misclassification error, for both FFQs were of similar magnitude and indicated that substantial attenuation of logistic regression coefficients would result from either FFQ. Our results confirm previous analyses describing the validity and utility of the 60-item FFQ (Epidemiology 1, 58-64, 1990) and indicate that it is essentially equivalent to the 100-item FFQ for epidemiological analyses of major nutrients.

Epstein‐Barr virus seroreactivity among unaffected individuals within high‐risk nasopharyngeal carcinoma families in Taiwan

Most adults have been infected with EBV. Many studies have indicated that antibodies against specific EBV antigens, particularly IgA antibodies, can be predictive or prognostic of EBV‐associated malignancies, such as NPC. We hypothesized that healthy individuals from families with a history of multiple members affected with NPC (who therefore might be genetically susceptible to NPC themselves) might have an EBV antibody profile that is distinct from that seen in healthy individuals from the community at large. To explore this possibility and examine determinants of anti‐EBV antibody levels in healthy, high‐risk individuals, we evaluated data from 2 parallel studies of NPC in Taiwan, which included 1,229 healthy members of families in which 2 or more individuals were affected with NPC and 320 controls from the community at large. Blood collected from participants was tested for IgA antibodies against EBV VCA and EBNA‐1 and for neutralizing antibodies against EBV DNase using standard assays. We observed evidence of familial aggregation of EBV seroreactivity among individuals from high‐risk, multiplex NPC families. Anti‐VCA IgA and anti‐EBNA‐1 IgA antibody seroprevalence in unaffected family members of NPC cases was 5–6 times higher than in members of the community (p < 0.01). This elevated seroprevalence among unaffected individuals from high‐risk families was observed regardless of the relationship of the unaffected individual to the closest affected relative (siblings, parents, children or spouses). No sociodemographic or environmental factors examined were found to strongly and consistently correlate with elevated seroprevalence, but patterns emerged of increasing seroprevalence among older individuals and among females. Unaffected individuals from high‐risk NPC families have elevated anti‐EBV IgA antibody titers. The etiologic and clinical implications of this finding remain to be established.

Development of a Computer-Assisted Personal Interview Software System for Collection of Tribal Fish Consumption Data

The authors developed a computer-assisted personal interviewing (CAPI) seafood consumption survey tool from existing Pacific NW Native American seafood consumption survey methodology. The software runs on readily available hardware and software, and is easily configured for different cultures and seafood resources. The CAPI is used with a booklet of harvest location maps and species and portion size images. The use of a CAPI facilitates tribal administration of seafood consumption surveys, allowing cost-effective collection of scientifically defensible data and tribal management of data and data interpretation. Use of tribal interviewers reduces potential bias and discomfort that may be associated with nontribal interviewers. The CAPI contains a 24-hour recall and food frequency questionnaire, and assesses seasonal seafood consumption and temporal changes in consumption. EPAs methodology for developing ambient water quality criteria for tribes assigns a high priority to local data. The CAPI will satisfy this guidance objective. Survey results will support development of tribal water quality standards on their lands and assessment of seafood consumption-related contaminant risks and nutritional benefits. CAPI advantages over paper surveys include complex question branching without raising respondent burden, more complete interviews due to answer error and range checking, data transcription error elimination, printing and mailing cost elimination, and improved data storage. The survey instrument was pilot tested among the Quinault Nation in 2006.