Article Critique

Introduction
The purpose of the study was to compare access to healthcare, use of healthcare services, and healthcare experiences for undocumented Mexicans and other undocumented Latinos. In the wake of policy debate over immigrant overuse of health services in the United States, the study is an important tool that policy makers can use to assess the impacts of immigrants on public services such as healthcare (Ortega, et al., 2007). In aIDition, the study is significant in evaluating the healthcare experiences of undocumented immigrants in the United States, which acts as a framework for customizing public policy to either accommodate or restrict immigrant use of public resources in the US. The specific aims that the research aimed at aIDress were threefold: to determine whether undocumented Mexicans and other undocumented Latinos use health services differently; whether they report different patterns of access; and whether they report different healthcare experiences.
Literature Review
            The study by Ortega et al (2007) reviewed the focus of prior studies regarding the policy debate associated with undocumented immigrants. The literature review is organized in a logical sequence resulting in a critical review and identification of research limitations of previous studies in order to support the specific aims of the study. In support of the research aims proposed in the study, Ortega et al (2007) points out that there is little empirical information provided in previous literature regarding healthcare experiences for undocumented immigrants. Despite the fact that studies have highlighted patterns of healthcare use by Mexican and Latino immigrants, there is little information about the variations in terms of documentation status. In aIDition, past studies that have attempted to tackle the issue used relatively small samples and limited healthcare variables, resulting in inconclusive data. (Ortega et al, 2007, p. 2354). The relationship with past studies is that this research aim at clarifying healthcare patterns, uses and experiences of immigrants according to documentation status and diversified healthcare measures, an aspect that prior studies ignored through generalization of the samples. In aIDition, the study aimed at examining the immigrants basing on national origin and ethnicity. It is arguably evident that the researchers described the gaps in the available literature to support the need of the present study.
Theoretical Framework and Hypothesis
            A significant flaw in the study is that the researchers failed to outline a rationale for the conceptual framework. This is possibly because the study was conducted with the aim of exploring aspects that previous study had failed to consider. The researchers clearly stated the theoretical basis for the hypothesis formulation. Ortega et al (2007) states that the CHIS offers a unique and timely data on a large sample of the populations basing on the assumption that there is little empirical information relating to healthcare access, patterns of use and healthcare experiences. Given the explorative and descriptive nature of the study, there was no need to formulate a hypothesis to be tested or to determine a casual relationship or inference between variables.
Methodology
            The study was descriptive with a clear definition of variables. The independent variables were ethnicity, immigration authorization status and national origin of participants. The dependent outcome variables/measures were use of physician and emergency department care, problems in obtaining basic care, having a usual source of care and three experiences with healthcare (Ortega, et al., 2007). Analysis was conducted to ascertain the relationship between immigration authorization status and the outcome measures among the participants. The research design can be argued to be implicit because the study simply aims at finding answers to the research questions by collecting and analyzing evidence. Overall, the research questions aimed at exploring the patterns of access to healthcare, variations in the use of healthcare and experiences among the undocumented Mexicans and other undocumented Latinos in the United States. The study used data secondary data sources from California Health Interview Survey, which is a random telephone survey of households in each county in California (Ortega, et al., 2007). The data collected was analyzed to support the aims of the study. The potential threats to the internal and external validity present in the study include lack of use of primary data. The study is somewhat analytical and does not entail a first-hand approach to gather information to document the healthcare experiences of the participants. Some elements of the research questions require more than just analysis of secondary data. For instance, the study should have used primary data sources through interviews and questionnaires to document the variation in the healthcare experiences of the participants.
Sample
            The CHIS, which was the source of data for the study, made use of a random survey of the households in California. The results were stratified to generate adequate sample for the study. The 42044 participants served to represent the non-institutionalized households. The participants in the study were classified basing on ethnicity, immigration authorization status and national origin. Given the number of outcome measures and design, it is evident that the sample size of 40,044 participants was sufficient for the study.
Data Analysis
            Data analysis was done using commercially available software. The chi-squared test was used for describing the sample population in terms of health insurance, documentation status, demographics and ethnicity. In aIDition, chi-square and variance analysis were used in comparing healthcare access measures (usual source and care and difficulties in accessing basic care) and use of healthcare services. A comparative analysis on healthcare experiences was also conducted. A multivariate analysis reported that undocumented Mexicans had 1.6 less doctor visits with P