Extrusión del compósito polietileno-aluminio

The sample was recruited from attendees of a hospital dietetic clinic in London. I recruited the sample, on two days each week, over a ten-week period. The clinic attendees were referred for help in losing weight to improve their health or medical condition. I confirmed this by examining the referral letters for the patients who were due to attend each clinic. This enabled the small proportion of patients attending the clinic for other reasons, e.g., for help with weight gain or help with a specific medical condition for which obesity was not a stated target for treatment, to be identified and not approached to take part in the study. Only patients between 18-65 years of age were included. I then approached patients in the waiting area of the clinic, introduced myself, explained the nature of the study, and gave them written information about the study and a consent form (presented in Appendix V). If the patient chose to take part, they were asked to sign the consent form, after which they were given a questionnaire to complete as they sat in the waiting area, or to take away and post back in a prepaid envelope that was provided.

5.2 Participants

Out of the 48 patients who were invited to take part, 41 (85.4%) completed the questionnaire. Of the seven patients who did not take part, one (2.1%) refused to take

part, two (4.2%) did not complete the questionnaire because of language difficulties and four (8.3%) did not post back their questionnaires. The demographic details of the Clinical Study participants are presented in the Results section.

5.3 Materials

The questionnaire was the same as for the Community Study, except that the questions about Down's syndrome were omitted (presented in Appendix V). This is because these questions had already been answered by the Community Study sample and including them in the Clinical Study would not have been on the basis of a priori hypotheses.

6. EXPERIMENTAL STUDY

6.1 Procedure

Participants of the Experimental Study were undergraduate students reading an Arts subject, at a university in England. I invited the students at the end of one of their lectures to volunteer to participate in a study into people’s beliefs and attitudes about obesity. Written information was handed out about the study along with a consent form and questionnaire (presented in Appendix VI). Two versions (Intervention and Control) of the questionnaire were sorted at random prior to administration. Participants then received one of the versions of the questionnaire to complete.

6.2 Participants

Of the 125 attendees at the lecture, 2 (1.6%) returned a questionnaire that was incomplete, with the remaining 123 (98.4%) returning a questionnaire that was included in

the study. The Intervention group was made up of 62 respondents and the Control group 61 respondents.

6.3 Materials

This Experimental Study used shortened versions of the Community Study questionnaire. The items omitted were not central to addressing the question of whether or not, beliefs and attitudes expressed about obesity are affected when presented with different information about the condition. Section C about Down’s syndrome," and the questions about education in Section D were omitted.

There were two different versions of the questionnaire; one was the “Intervention” and the other “Control.” The Intervention version communicated to respondents a clear and strong genetic link in the development of obesity. The Control version did not mention genetic factors. The information was given in the form of six ‘facts’ or statements about obesity (“Obesity Matters”) preceding the questions on the questionnaire. There were two versions of these facts - Intervention and Control (presented in Table 2.1 on the following page). The versions had three facts in common on the epidemiology of obesity and three additional facts. In the Intervention version, three additional facts concerned the links between genes and obesity were inserted. In the Control version, the three additional facts concerned the epidemiology of obesity and did not mention genetic or other causal factors.

TABLE 2.1. The ‘facts’ about obesity presented at the top of the questionnaires in the Experimental Study.

Control version Intervention version

1. Obesity means having an excess of body fat, measured as being approximately 20% over the ideal weight for height

2. Almost 20% of adults in Britain are now obese

3. Obesity increases the risk of heart disease, cancer and diabetes

4. Obesity is more common in women than men

5. Obesity has become more common in Britain over the past 50 years

6. Obesity risk increases with age

1. Obesity means having an excess of body fat, measured as being approximately 20% over the ideal weight for height

2. Obesity increases the risk of heart disease, cancer and diabetes

3. Almost 20% of adults in Britain are now obese

4. Adoption studies show that children adopted at birth are more similar in weight to their biological parents (birth family) than their adoptive parents

5. Genetic research shows that genes account for most of the variation irt obesity across the population

6. Geneticists are beginning to identify the genes which cause obesity

Following the facts, three questions were added that asked about three of the facts. The aim of these questions was to assess whether the stimulus material had been read. The respondent had a choice of two answers, a correct and incorrect answer, with the correct answer being clear from the information. Two of the questions were the same on each version of the questionnaire. The third question on the Intervention version focussed on the genetic facts about obesity. The third question on the Control version concerned one of the epidemiological facts.

The Intervention and Control versions of the questionnaire are presented in Appendix VI.

6.4 Design

The two versions of the questionnaire were ordered randomly prior to being handed out to the students at the lecture. Participants who completed the questionnaire containing information on the genetic links to obesity comprised the Intervention group. Participants

who completed the other version of the questionnaire which did not include information on the genetic links to obesity comprised the Control group.

The independent variable was the version of questionnaire completed (Intervention or genetic version and the Control or non-genetic version). The dependent variables were responses to the questionnaire, specifically responses to items concerning beliefs about the causes of obesity, the attributions about obesity, and attitudes toward people who are obese.

CHAPTER 3

Results

1. OVERVIEW

I open this Results section with a brief note about the methods of data analysis employed. The descriptive and inferential statistics are then presented in four sections: the results from the Community, Reliability, Clinical and Experimental studies.

For the three main studies (i.e., not the Reliability Study) demographic details and bodyweight statistics are presented first. The main statistics for each study follow. I present statistics on the beliefs about how genetic and controllable human characteristics are in general. Then I present beliefs about the role of genes as causal factors in obesity along with beliefs about the role of other causal factors, attributions about the obese and attitudes towards people who are obese.

An effort has been made to present the main information gathered and the data that are relevant to answering the research questions. In addition to keeping the Results section more concise and focussed, this decision will help to decrease the likelihood of type I error.