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The purpose of the Barbados Food Consumption and Anthropometric Survey (2000) was to determine the food intake and dietary patterns of the country's adult population, the prevalence of obesity and diagnosed nutrition-related CNCDs, and the relationship between these and dietary patterns. The information obtained through this study will enable NNC to plan and execute various targeted intervention programmes with the aims of increasing the population's levels of awareness of health-related risks and of actually reducing those risks by adopting more appropriate eating and lifestyle patterns.

The specific objectives of the survey were to:

Survey methodology

This survey was designed to provide national results at a 3 percent tolerance with a 95 percent degree of confidence. The sample design was a systematic random two-stage cluster design.


Selection of households

The first stage involved the selection of 42 Enumeration Districts (EDs) from a total of 547. In the second stage, 13 clusters of three households each were selected systematically within each of the 42 selected EDs. Each cluster consisted of a primary household and two secondary households. The secondary households were the households immediately before and immediately after the primary household. A total of 1 638 households were selected, and 1 051 were in the final sample (see the section on Recommendations for future surveys: difficulties encountered and limitations of the survey). Enumerators reported that several of the houses were vacant, or occupied by tourists on a short-term basis. The occupants of some houses refused to participate.

The sample was selected from the EDs that were used by the Barbados Statistical Service (BSS) for the population census in May 2000. These EDs had been created to include approximately 150 households each - EDs used in previous population censuses were divided in order to ensure this. Each ED thus had an equal probability of selection.

The EDs were first ordered from the northwestern corner of Barbados, moving in a serpentine fashion to the east and south, with the last ED listed being located in the southeastern corner. Only households in these EDs were enumerated. In each selected ED, the 13 clusters of three households were selected systematically with a random start.

Selection of individuals

Two people of at least 18 years of age were interviewed in each household, except in one-person households or in those where only one person was 18 years or more. The head of the household or the person who prepared the meal was interviewed for the household questionnaire and the first individual questionnaire. A second individual questionnaire was administered to a second person who was selected randomly according to the rules set out in the survey manual.

In general, interviewers conducted household visits in pairs to facilitate the weighing and measuring of the respondents, but this practice was not always possible and some households were visited by only one enumerator. Interviewers were advised to leave a callback card at the households of people who were not at home asking them to contact NNC; however none of these prospective respondents called. The interviewer made two follow-up visits, and if contact was not established, "refusal" was indicated on the questionnaire, which was given to the supervisor.


The survey team consisted of three supervisors, to each of whom was assigned a group of 12 enumerators at the start of the data collection phase. The enumerators included community nutrition officers, a dietetic technician, a school meals supervisor, nurses, an environmental health officer, agricultural field officers and field and supervisory staff who had recently been employed on other surveys.

It was the responsibility of each supervisor to identify and indicate the 13 clusters of households in each ED to the enumerators. In most cases, two enumerators visited each household, but there were instances when only one interviewer visited in order to ensure that the identified respondents were interviewed as scheduled. Interviews were conducted in the evenings and at weekends, as well as during regular working hours.


Three standardization and training workshops were conducted for interviewers, who were taught skills for conducting interviews and for collecting anthropometric and dietary intake information. Each received a copy of the Interview manual for Barbados, which was the reference document during the sessions. Consultants from FAO and the Caribbean Food and Nutrition Institute (CFNI), and technical staff from BSS and NNC were the resource persons at the standardization workshops. Data collection commenced on 5 September 2000.

Interviewers were trained to:

After the first workshop, the interviewers pilot-tested the instrument in parishes that BSS identified as having similar demographic profiles to those in which the survey would be conducted. Following the pilot tests, the consultants and other resource persons made adjustments to the instrument as required.

A second pilot test was carried out, and discussions were held with the consultants and interviewers before final changes were made to the instrument.

The following quality control measures were implemented during data collection for the survey:


The following two questionnaires were used to gather the information for the survey:

In addition, anthropometric measurements were taken. The interviewers were trained to perform standard anthropometric assessment. Each individual was weighed and measured twice. When the difference between the two measurements was within pre-set limits, the second measurement was recorded. Body weight was recorded to the nearest half pound (converted later to kilograms) with an electronic scale, and height was measured to the nearest centimetre with a metal measuring tape and a stadiometer.

A 24-hour recall period was used to determine each individual's food intake in the 24 hours prior to the interview, using a standardized four-step protocol: 1) a complete list of all foods and beverages consumed during the previous 24-hour period, or preceding day, was obtained; 2) detailed descriptions of all the foods and beverages consumed, including cooking methods and brand names (if possible), were recorded; 3) estimates of the amounts of all foods and beverages consumed were obtained, using household measurement equipment such as kitchen spoons, cups and kitchen scales; and 4) the interviewer reviewed the recall with the respondent to ensure that all items had been recorded correctly.

In addition, a semi-quantitative food frequency questionnaire with a list of 84 foods was administered. Frequency was coded as daily, weekly, monthly or none, and the number of predefined measuring units consumed was recorded. A measuring unit, approximated by staff from NNC in collaboration with the CERES[5] consultant, served as a reference portion from which the enumerator determined the amount that the respondent stated he or she had consumed, according to the frequency of intake specified. Portions were also recorded in grams, as required for foods that were recorded by weight.

A pilot study was conducted to validate these methods. Interviewers were provided with a bag containing household equipment such as a kitchen scale, measuring cups and spoons to help respondents recall the quantity of foods eaten. For food items such as carbonated drinks and juices packed in boxes, a chart was prepared showing the amounts in each container of various beverages.

Data processing and analysis


Supervisors and a team of nutritionists checked the 24-hour recalls and the semi-quantitative food frequency questionnaires before two trained data entry clerks entered the data. As a quality control measure, the CERES consultant randomly selected and entered 200 of the completed questionnaires in order to compare this with the data entry carried out by the clerks. Household measures were converted to grams and used to record quantities of cooked or raw food, as appropriate. A preliminary data analysis (frequencies and histograms) was used to identify errors and outliers, which were then corrected or recoded as missing values. The Statistical Package for the Social Sciences (SPSS) Version 8 was used for all data analysis.


The CERES computer program was used to determine the nutritional value and nutrient adequacy of the diet, using Food composition tables for use in the English-speaking Caribbean (FCT) and Recommended dietary allowances for the Caribbean (RDA) (CFNI, 1993 and 1998).

The nutritional value and adequacy of the diet was calculated from the 24-hour recalls. The semi-quantitative food frequency questionnaire was used to examine dietary diversity and to identify the best food sources for the nutrients.

The nutrient compositions of some frequently consumed local recipes were calculated and added to the food composition table in the CERES program. Local foods were also grouped into the "generic" classification and installed into the CERES program. The calculation of the 38 generic foods (see Annex IV) was based on the quantities used in FCT.

RDA was used as the standard against which the adequacies of energy and selected nutrient intakes for each respondent were assessed. Four age groups were used in analysing the results: 18 to 29 years (<30 years); 30 to 49 years; 50 to 64 years; and ³ 65 years.

Using the information collected from the 24-hour recall and the CERES program, the following information was obtained:

Based on World Health Organization (WHO) standards, percentages of adequacy of respondents' energy and nutrient intakes were categorized for the analysis into the following categories: £ 70 percent (very inadequate), 70.1 to 90 percent (inadequate), 90.1 to 110 percent (adequate) and > 110 percent (excessive). Adequate dietary protein, fats and carbohydrate intakes as percentages of total energy were determined and categorized as follows:

The nutrient goal for fruits and vegetables was set at 370 g per day. Two scores were developed: 1) the micronutrient adequacy score was calculated from the levels of adequacy of a range of micronutrients, using data from the 24-hour recalls (see the subsection on Micronutrient adequacy in Chapter 3); and 2) the dietary diversity score was calculated from the number of items consumed and the frequency of their consumption, using data from the food frequency questionnaire (see the subsection on Dietary diversity in Chapter 3).

Body mass index (BMI) was calculated from each respondent's weight and height according to the following equation:

BMI = weight (kg)/height (m)2

The standard WHO/FAO classification was used to define underweight, normal weight, overweight (also called pre-obesity), and obesity classes I to III (see Table 3.11).


Statistical analysis was performed using SPSS Version 8. Frequency distributions, medians, means and standard deviations were used to describe the data. Cross-tabulations and chi-squared tests were performed to evaluate the strength of association between categorical variables, especially to examine differences across age groups and sexes. For continuous variables (such as BMI and dietary intake data), t-tests and one-way analyses of variance were used to investigate differences between age groups and sexes. In all cases, p < 0.05 was used as the cut-off for statistical significance.

Vulnerability profiles were developed using a number of definitions of vulnerability (see Chapter 4). This was done either by performing multiple regression analyses to determine the contributions of a range of variables to the variation of certain key indicators (BMI, micronutrient adequacy scores and dietary diversity scores), or by using t-tests, one-way analyses of variance and chi-square tests to examine other potentially vulnerable conditions (poverty, old age, and female-headed households). The results of in-depth analyses of three key issues - iron deficiency anaemia, healthy lifestyles and younger adults - are presented in Chapter 5.

Throughout this report, the results from the Barbadian survey have been put into context by comparing them with earlier Barbadian data (to examine trends), with data from other Caribbean countries and, in some instances, with data from the United Kingdom or the United States. Chapters 3, 4 and 5 focus on significant findings, rather than presenting the results of all the analyses undertaken. Chapter 6 presents the policy and programmatic implications, as well as recommendations based on the survey results.

Recommendations for future surveys: difficulties encountered and limitations of the survey

A national survey such as this one requires considerable forward planning. It demands a substantial commitment of time and resources, and should therefore be undertaken only when adequate time and resources exist and when the survey results will be put to good use in guiding policy construction and programme planning. It is useful to examine the planning and implementation of this survey in order to extract lessons learned that might benefit future surveys. The following recommendations are based on the experience of a survey that was successfully executed by NNC. Many of the lessons learned, difficulties experienced and limitations of the data are by no means unique to this survey, and can be found in textbooks on survey methodology, especially those on dietary methodology and nutritional epidemiology. However, it is helpful to consider them in the context of this survey.



[5] CERES is the software package that was used to analyse the food intake data. It was developed by the Instituto de Nutrición e Higiene de los Alimentos in Havana, with funding from FAO, and incorporates the Caribbean food composition tables.

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