Question 3
- Photographs used in this study were not labeled with portion size information. In the existing ASA24 (automated, self-administered 24-hour dietary recall), however, portion size images are routinely labeled with common units such as ounces, cups, etc. Do you think the accuracy of the participants’ answers in this study was affected by use of photos with no size labels assigned or would this fact not matter? Why?
posted by Alison Geyer @ 9:12 AM
28 comments
28 Comments:
I think that the accuracy could have been affected only for individuals who cook and/or who are familiar with common units such as ounces or cups. Based on the fact that 1/3 of the participants chosen for the study were lower literacy individuals, I do not think that the labeling differences would have affected the accuracy of the participants' answers.
I think not having the size probably made it more accurate. It is less alarming and I think that the client would be less likely to make something up if they see a picture as opposed to saying I ate 6cups of spaghetti. If I had to guess I would actually say that the pictures probably gave a more realistic account of what they were eating.
Anna,
You are so right. There are not many people who are currently in the kitchen cooking so knowing the cooking units would not be neccessary or even known by most individuals. I would have not even thought of that as affecting the accuracy.
I do not think that labeling the photographs would have made a difference. For most people, I would think seeing a visual aid (photographs of different portion sizes of food) is much easier to apply to their own intake of those foods than using unit sizes. Many individuals are not familiar with what a cup looks like of a particular food; let alone how many ounces are in that food portion. If anything, I think using actual photographs makes the 24-hour recall answers more accurate.
I agree with Melanie. Most people do not know how much a cup or ounce actually is; I feel that their concepts of these measurements would skew their answers. In other words, having the portion size information labels alongside the pictures would only confuse the issue in many cases. As Shelby said, lots of people will easily eat several cups of pasta, but would not think it had been that much and might guess it had only been one cup instead of 3, leading them to select using the measurement labels instead of the illustration.
If I were to imagine looking at two photographs, one with just food and one with food and its measurement underneath, than I think that the picture with the measurement would look like a larger amount to me. It is likely that the participants would underestimate their intake. As Shelby said, it is more alarming to see the measurement next to the item. Most people don't realize how much they really do eat because of the current enormous portion sizes, and they may feel some guilt and try to round down.
Again, I kind of see two different views when I think about answering this question. On one hand, I think the accuracy of the participants' answers in this study wasn't affected by use of photos with no size labels assigned because most people who haven't had much education with nutrition don't really know what the sizes mean anyway-they are only guessing about how many 1/2c servings of spaghetti they had without any real concept of what 1/2 cup of pasta means. But on the other hand, the participants who do understand portion sizes could report much more accurate data if they had size labels assigned to the photos.
Overall, I do not think that including common units with the photographs would have increased the subject’s accuracy when choosing portion sizes. Many people are not familiar with common units such as cups, ounces, etc. and this may just confuse them further. Of course, there are certain people who would be able to more accurately indicate their intake by using a common unit of measurement versus a photograph. But overall, I think with the general public it would be best to only include the photographs to achieve the highest percentage of accuracy.
I agree with Nicole. I think that for most people including a common unit would lead them to underestimate their intake. Using this method would just make 24-hour recalls more difficult for the subjects and they would still be inaccurate, which means they would have to be completed again with assistance.
I feel that the participants’ answers would be more accurate without serving sizes present. When someone is unaware of the serving size of something they ate, they would probably be more truthful in recording the actual amount just based on a photo. If there was a serving size present, I feel that a participant would be more aware if they overate, possibly leading them to alter their response.
I completely agree with Nicole. I think that the picture with the measurement would look like a larger amount to me, as well. I think that the majority of people, who aren’t familiar with cooking or serving sizes, underestimate their food intake.
I think that showing the measurement amount would probably have too much of an effect on the subjects answers and it would void the purpose of the study. The point of the study was to see which (if any) pictures were helpful and accurate enough to use on a 24 hour recall site. Having the numbers might have made the subjects focus more on the portion numbers than what the picture is trying to show them. So, I think that not having labels might have affected the accuracy of the answers in the study, but I think not having them helped the researchers decide if the pictures were effective.
Anna-
I think you are right. Individuals who cooked or are very familiar with common units would probably benefit the most from the units being shown with the pictures. I did not even think about the possibility of someone not knowing some of the units or about how much they are.
I do not think the accuracy of the answers was affected by using photographs with no size labels assigned. In fact, I think that it was probably more accurate to use these pictures without measurement labels, because generally people underestimate what they are eating when talking in terms of measurements. Therefore, I feel like if people looked at what they thought they were eating based on the picture, and then realized that the picture was three times the amount they thought that it was, they might be tempted to pick the picture of the smaller serving size simply out of guilt. I feel like this could really sway the study results.
Shelby,
After submitting my response, I realize that we have pretty much the same thoughts on the matter. I totally agree that people were probably giving a more accurate picture of what they are eating based on the photographs than they would have if they would have seen the measurements.
In my opinion, I feel that providing the portion sizes really would have made no difference in the accuracy of the participants answers. Providing both the image and the correct label would be beneficial in educating the participants on what certain portion sizes look like but overall, I feel their answers would not have changed. Providing an image of something, in my opinion, is much easier to interpret and identify rather than providing a label, especially labels that many people are unfamiliar with such as what 8 ounces or 1 cup of something looks like so although some people may have had any easier time with labels included, in general, this fact would not have mattered.
I agree with Liz when mentioned that providing the labeled portion sizes may cause people to falsify their responses out of embarassment of what they actually consumed. However, I feel this thought process could also be applied to providing images of the portion sizes. Some people when hearing two cups may think that that doesn't sounds so bad but when they see an image of what two cups of pasta, cheese, ect actually looks like then they may be prone to lying and choosing the less threatening and smaller portion to make themselves feel better.
I think that the participant's answers in the study were probably more accurate, than if portion size labels were used. Portion size information labels may affect the way a participant answers. He/she may want to think that have eaten more/less than the unit labeled. Another study should be done comparing the effects of labeling, and not labeling. However, I do think the study should have been conducted exactly how the existing ASA24 will be administered.
Nicole, I definitely agree with you in that most individuals underestimate their portion sizes. Therefore, I think that by having a common unit underneath the picture the accuracy of the participants answers may be flawed, especially for the general public.
I feel like not having the pictures labeled doesn't affect the accuracy of the portion size estimates. A lot of people don't measure their food when they are eating a meal so most people were probably going off of the visual picture they remember when they ate the meal to determine the portion size.
I agreee with you Melanie about the fact that most people don't know what 1 cup of a certain food looks like and if they were shown that they probably wouldn't believe it. That has been my experience in the past when working with patients and food models.
I think that putting numbers and measurements would throw people off and most likely cause them to answer differently. They might see a serving of a cup of rice without the measurement and think that is about how much they ate, but if they saw the “a cup” attached to the picture they might think they ate less than that because a cup might sound like a lot to them. I feel that people are more likely to honest with their responses when they are unaware of the actual size because some individuals have a hard time admitting how much they eat.
I feel as though the ability of participants to use size labels or pictures or the combination of both varies. If one feels pictures are easiest to relate to they may second guess themselves with size labels and alternatively, if one feels comfortable with size labels they may second guess themselves with the pictures. Yes, not having size labels could have affected the accuracy of the participant’s answers leading to additional inaccuracy issues involved with 24-hour recalls, however; I am doubtful this affect would be significant. Maybe they should be asked a preference of which method they feel more comfortable comparing their intake to.
Anna, I agree completely. I did not consider literacy in my initial thoughts. This information seems essential for determining whether the labels would have affected the accuracy of the answers.
I think that labeling the photographs with the portion measurement would negatively affect the accuracy. The goal of the study was to determine the effectiveness of photographs on subject's 24 hour recall, not portion labels, so adding the labels would only confuse participants and detract from the quality of the study.
-Sarah Gervais
I think not having the portion size could have impacted the results. However, most people don't visually know what a cup or tablespoon looks like. So, the question is, which way would have the labels impacted the results? Would they have been more accurate since people could see the measurement as well? Or would they have been worse because they would they would see a portion (that was accurate) but think 'there is no way I ate a cup!'? I think its a double edge sword.
Kara, I think you hit the nail on the head. Including labeling would probably cause many people to second guess their initial reponses according to their personal concepts of different such as one cup, one teaspoon, etc. Using only the picture as a basis for selection will probably make a more consistent (aka reliable) tool, as a person may overestimate what a cup is, while underestimating what a tablespoon is. Using simple visual comparisons may not result in accurate (valid) selections, but would probably increase the reliability of the participant's responses.
I agree with Sarah G. that using portion sizes negatively affect the accuracy and that using photographs was what was being studied in this instance. Rachel, I also think you made a great point. Some people might measure their food so having portion sizes would allow them to be more accurate. But others may second-guess their answers if they saw a portion size with it.
Post a Comment
<< Home