Article ecological

1. Start with the article title. Is the title clear? Does it tell you the topic of the article, including the E, D/O, and P ? How do you think you would improve it?

2. Next, read the abstract. What is the format of the abstract – structured or unstructured?

3. There are 3 columns of text on the first page making up the Introduction section. The Introduction section comprised of 5 paragraphs.

a. * In Paragraph 1, the last sentence cited references #2 and 3 (the small numbers listed in superscript). Go to the reference section of this article and look at what citations #2 and 3 are. What do you of the appropriateness of these two citations for this sentence in this article?

b. * In Paragraph 2 of Introduction, the authors made a case for the importance of studying tuberculosis from an ecological standpoint. What did the authors mean by that, and can you rephrase the authors’ reasoning for studying ecological tuberculosis in your own words?

c. * In Paragraph 3 of Introduction, the authors quoted the definition of a census tract. Without quoting, paraphrase that definition in your own words (think of it as explaining it back to yourself in plain language):

d. * In Paragraph 4 of Introduction, the authors explained their reasoning for choosing children as the study population instead of adults. Can you explain their reasoning in plain language, in your own words?

e. * In paragraph 5 of Introduction, the authors justified their choice of California as the study location. Do you agree with their reasoning? Why or why not?

4. * Now that you have read the Abstract and Introduction sections, with as much detail as possible, can you state this research article’s:

a. Exposures:

b. Outcomes:

c. Population:

5. Now, move on to the Methods section.

a. * In the first subsection called “Data Collection: Tuberculosis Cases”, the authors described where they obtained the TB cases for their study. Based on this description, would you consider this analysis primary, secondary, or tertiary? Explain your reasoning.

b. * In the second subsection called “Data Collection: Ecological Measures”, under paragraph 1 and in Table 1, the authors described different measures and their respective operational definitions which they obtained from the 2000 US Census website. Why were these specific measures chosen for analysis in this study (i.e., why did they choose to include measures like demographic, education, occupation, economy, housing)?

c. * In the second subsection called “Data Collection: Ecological Measures”, under paragraph 2 and in Table 2, the authors showed the means, standard deviations, and ranges of those specific measures that they’ve previously described.

i. How many census tracts in California were used for analysis purposes in this study?

ii. Table 2 is what we typically call a “descriptive statistics table”. Here, are these descriptive statistics representing the characteristics of individual study participants? Why do you think so?

d. The “Statistical Analysis” section of this article is extremely technical, so try reading through it once, but don’t worry about not understanding those technical details. However, there are still a few takeaway messages from this section: (i) the authors provided full disclosure on their statistical methods, and therefore a professional researcher would actually appreciate all these details; (b) the significance level they used is p=.05; and (c) the software they used for data analysis is called Stata, version 7.0.

6. Let’s move on to the Results section of the paper.

a. The Results section consists of written text in separate paragraphs as well as Table 3, and Figure 1 that has two graphs. The written results are also quite technical. Give it a read-through once.

b. * Now look at Table 3 under the column for "Full Multivariate Analysis". This table is showing you incidence rate ratio data (IRR) plus their 95% CI across four types of models: univariate, intermediate, full multivariate, and US-born only. Which variables (under "Area-based measure") were statistically significantly associated with pediatric tuberculosis? How would you know that they were statistically significant? (Hint: significance has something to do with the confidence intervals).

c. * Still on Table 3, look at the variable “Median Income”, which has a small description in the table footnotes. Can you explain what that footnote mean with regards to median income? Try saying what you think it means in your own words.

d. * Give an interpretation based on "Median income" and IRR=1.62 (95% CI=1.48, 1.78) for pediatric TB:

7. Finally, read through the long Discussion section of the paper.

a. * In paragraph 2 of the Discussion section under General Fin, the authors stated the following:

“This analysis is further support for earlier studies showing that minority race/ethnicity is a risk factor for disease. However, whereas previous research11 has suggested that the risk of race/ethnicity is largely secondary to its correlation with socioeconomic risk factors such as low education, high unemployment, crowding, and high population density, our data did not support this conclusion. In our multivariate analysis, the variability in cases of tuberculosis was better explained by immigration, racial/ethnic minority groupings, and median income than by other variables such as low education, high unemployment, crowded housing, and high population density. The risk of race for disease could be caused by a combination of factors.” (Myers et al., 2006, p. 688).

Paraphrase the information above in your own words (do your best):

b. * In this study the authors concluded that “Census tracts with lower median incomes, more racial/ethnic minorities, and more immigrants had higher rates of pediatric tuberculosis” (Myers et al., 2006, p. 685). What is an ecological fallacy that someone can make based on the results in this study?

8. Other information

a. * Who funded this study?

b. * Under “Human Participant Protection”, the authors stated, “No institutional review board protocol approval was needed for this study” (Myers et al., 2006, p. 690). Why do you think ethics approval was not needed?