Evidence exists for a universal set of symptoms associated with autism, and there is reliability in the diagnosis of ASD and the differences in subtypes (American
Psychological Association, 2000, 2013; Fombonne et al., 2004; Hill et al., 2001). . . . A more recent study by Magaủa and colleagues (2013) compared ADI-R scores in Latino adolescents to a matched group of non-Latino White adolescents. They found no
significant differences between the two groups on the Social Reciprocity and the Communication subscale scores, but they found a consistent difference between the groups in the Restricted, Repetitive Behaviors subscale score. The Latino parents reported significantly less impairment in this area. The authors note that it is difficult to determine whether these differences were attributed to actual behavioral differences between the two groups, or whether parents may have understood the items differently (Magaủa &
Smith, 2013). . . .
Here, they also emphasize the differences between studies: The first study found that Latino parents expect milestones later than other parents, whereas another study found that they expect children’s milestones at almost the same time as Anglo parents.
In the next section, the authors move even closer to their own topic. Here, they explore research focused on autism among Latino children.
Later in this section, the authors provide a bit more information about the nuances of a specific study that compares scores of social reciprocity and communication. They point out differences and say that it is unclear whether these differences are due to children’s behaviors or parents’ interpretations.
Building from previous studies illustrating the underdiagnosis of ASD among Latino children (CDC, 2006, 2014), the present study compares parents’ reports of ASD symptoms with clinician observations, in a sample of newly screened children with an ASD.
At the very end of the literature review, the authors tailor the direction of the discussion toward their study and how their study simultaneously completes the literature and sheds light on some new aspect.
Thinking Critically
Exploring different venues regarding how to design your literature review is always recommended, but one important principle should be kept in mind:
employing critical thinking. Using critical thinking is one of the reasons students go to school in the first place. Reading books and learning new information can help to gain knowledge. Some of that knowledge is retained and some is forgotten. Being critical, on the other hand, is a skill that can be applied to various aspects of life. But how can one be critical and what does critical thinking really mean?
Reading Critically
Critical thinking begins with critical reading of the literature. One of the best definitions of critical thinking is provided by Elder and Paul (2001), who define critical thinking as “the mode of thinking about any subject, content, or problem—in which the thinker improves the quality of his or her thinking by skillfully taking charge of the structures inherent in thinking and imposing intellectual standards upon them” (p. 19). One way of
thinking about this relates to passive versus active reading. When we read something because we have to, but have no interest in the topic, we often read it passively, simply trying to retain the information we are reading. Our mind wanders to other things and although we read the letters, words, and sentences and spend valuable time doing so, we are passively absorbing information. It comes as no surprise that we may not remember much from what we are reading because our attention and focus are not quite there. To put this bluntly, this type of passive reading is a waste of time.
Parents of children who exhibit ADHD-like behaviors often find themselves in the middle of a controversy, uncertain on how to interpret their child’s behaviors.
© iStockphoto.com/ferrantraite
There are other times, however, when we are reading something that grabs our interest. We are reading the information in front of us, but we are also simultaneously thinking and considering the information given. We may or may not agree with what we are reading and for each sentence that our eyes read, our brain also completes it with additional ideas, suggestions, or
illustrations. This is active reading, and it immediately leads to critical thinking because we are not simply absorbing the new information; we are agreeing or disagreeing with it and are offering our own arguments.
Critical thinking is one of those crucial skills that, if practiced enough, can become your way of reading everything. When writing a literature review, you are not simply reiterating information about the literature you read. You are raising questions, gathering relevant information, interpreting it through your perspective, and coming to logical conclusions about the material at hand. When thinking critically, you are evaluating the study you are
reading, constantly checking for different perspectives, and keeping an open mind about what is missing and how the problem is investigated.
Analyzing Studies
To analyze a study, first look at the concepts, theories, and perspectives the researchers are using by asking questions regarding their intentions and whether they considered other ideas about their work. Here, you need to pay close attention to possible assumptions that authors may have taken for granted.
Next, you look closely at the methodologies employed by most peer-
reviewed studies. The simplest way to remember the details of each study is to write down its methodological approaches (e.g., an in-depth interview with 35 participants of an average age of 30, a questionnaire distributed to 250 participants, a focus group with 10 participants). Often, these studies have similar methodologies and you may be able to draw a clear picture of the literature you are reviewing by pointing out the percentage of studies that used questionnaires, the number of studies that have more women participants, or other distinguishable characteristics. These details are necessary to not only portray your mastery of the literature, but also show how your study is of significance since you may be fulfilling a missing approach from these methodologies.
Let’s illustrate this point. There have been quite a few studies conducted on diabetic children and what type of treatment works best or what type of difficulties these children’s parents face in coping with their children’s problems due to diabetes. A novice researcher may review all of the studies and write down the methodologies used. Once this has been completed, it is easy to see that many studies use multiple-choice questionnaires to survey a large number of parents. You can also see from your table that most of the parents responding to the surveys are mothers. If you were thinking of conducting in-depth interviews with both parents to delineate the daily life for a parent of a diabetic child, you are in luck. You can clearly make the point that the literature is missing an in-depth understanding of this group of parents, their daily challenges, their frustrations, their joyful moments, and their achievements. You can also point out how the majority of the participants in the studies you reviewed are mothers. Therefore, the
literature is missing one crucial dimension: the perspective of fathers. This
type of argument makes your literature review much stronger, more
effective, and engaging. You are showing that you have knowledge of the body of literature you investigated, have found the missing gaps in it, and are contributing to the field by filling those gaps. You must look at the body of literature and find your niche. This process is simultaneously creative and exciting.
Hypotheses
The hypotheses of your study need to be included at the end of your
literature review. After all, that is why you wrote the entire argument with the literature. You needed to prove how important your hypotheses are and why this particular study is worth investigating. Often, the alternative and null hypotheses are placed in a separate paragraph. Remember our
discussion from Chapter 2 where we always try to reject the null
hypothesis. In a nutshell, that is the focus of our study, so we need to state these hypotheses at the end of the literature review.
For example, I am interested in conducting a mixed-methods study about the ways that psychiatrists diagnose their patients. My goal is to find out the process of how a person is diagnosed with any disorder or mental problem, as well as the percentage of people who walk in the door of a psychiatrist’s office, but are mentally healthy and leave without a diagnosis. Once the literature is explored and it shows that there is a disagreement among
researchers on whether some diagnoses are truly mental problems as well as the increasing number of people being diagnosed in our society, the
literature review clearly shows the need to explore this topic further. At the end of it are the hypotheses. The following is an illustration of this
example:
H1: There is a relationship between the number of complaints people express at the psychiatrist’s office when they walk in for the first time and whether they leave with a diagnosis. The relationship is one- directional, so the higher the number of complaints, the higher the number of diagnoses the patient receives.
H01: There is no relationship or trend between the number of
complaints from people who walk in to a psychiatrist’s office for the first time and the number of diagnoses they receive.
H2: There is a relationship between the number of complaints people express at the psychiatrist’s office when they walk in for the first time and whether they leave with a prescription for psychotropic
medications. The relationship is one-directional, so the higher the number of complaints, the higher the number of prescriptions.
H02: There is no relationship between the number of complaints of people who walk in to a psychiatrist’s office for the first time and the number of prescriptions they receive.
Systematic Reviews of Literature
A systematic review of the literature is different from a literature review. In fact, a good systematic review of literature has its own literature review. A systematic review is a form of scientific study. It is an attempt to bring together every scientific study on a specific topic and draw conclusions from it. A literature review tries to prove why the researcher’s topic is a topic that needs to be investigated and it is tailored to support the
researcher’s study. A systematic review has no such agenda. It is focused on synthesizing all the literature on a topic. Let us look at the differences
between a systematic review and a literature review for a better understanding.
Systematic Reviews Versus Literature Reviews
There are four major differences between a systematic review and a literature review, which we will discuss in detail here.
(a) The focus is different.
When we conduct a study on a topic that interests us, we are prone to have collected studies that support our ideas or even read scientific reports we find appealing. Sometimes we may even disregard or not pay close
attention to a study that investigates something completely different from what we are trying to accomplish—and we do this unintentionally—mostly because we are truly dedicated to our topic. This translates, however, into a literature review focused to serve the study we are undertaking rather than a review of literature for the sake of review. A systematic review focuses on systematically collecting together every scientific study in a topic of interest and evaluating them. The focus of the systematic review means conducting the best review possible rather than using it to serve another study. This basic differentiation between these two forms of reviews is at the root of the rest of the distinctions between the two.
(b) Selection bias is reduced.
A systematic review follows specific guidelines in collecting studies on a topic. This means systematic reviews are less prone to biases, such as
selection bias, that may result from choosing different studies as is done in traditional literature reviews. Selection bias refers to the researcher’s
tendency to look closely at scientific articles or scientific work that aligns with that researcher’s ideas about a topic and overlooks other work that may oppose these ideas. The lack of biases and thoroughness of systematic
reports are what makes these pieces of scientific reports very attractive. A systematic review reports exactly how many databases were searched, the rationale of choosing those specific databases, what keywords or
combination of keywords were used, and how many results each search yielded. They are inclusive of all the studies that fit the predefined criteria
of searching. The researcher cannot decide against including a study in the review without a specific reason that needs to be reported.
Traditional literature reviews are not as strict, although it is widely believed that most researchers follow exactly the same steps for traditional reviews and that a strong traditional review has some elements of the systematic review incorporated in it. However, since criteria for traditional reviews change, there exists the possibility for potential selection biases.
(c) There are rigorous steps and procedures.
A systematic review of literature is a research study that focuses on other scientific studies. To put things in context, the scientific studies that are examined from a systematic review of literature are the participants of the study. As such, conducting a systematic review implies following rigorous steps and procedures to achieve the best quality possible. When we extract scientific studies for traditional literature reviews that are supporting
specific research, we go to various databases, try different keywords, look at studies that we find from the references of a major study, and so on. We rarely keep a strict record of how we found out about these studies and what databases we used. These steps and procedures on how to extract scientific studies on a topic are extremely important for a systematic review of
literature. This is the methodology of the systematic review because it answers the question on how the data were collected—in this case how the studies were collected—what sources were used and why, how the
researcher made the decision to include specific articles, but leave out some others. In other words, the methodology of systematic reviews is the
methodology used to establish that the collection of articles in a topic is sufficiently inclusive, unbiased, systematic, and following methodological guidelines.
(d) Assessment and analyses of studies are involved.
A traditional literature review will often provide some information on one or two studies and will summarize the conclusions of another study,
depending on how the researcher has designed the review. A systematic review of literature will collect all the methodologies of all the studies, conclusions, and discussions and will provide summaries as well as
analyses of these scientific studies. In other words, it will thoroughly investigate the data from all the studies and provide detailed information about these studies and their similarities and differences.
Meta-analyses and systematic reviews of literature are very similar, with one important difference. Meta-analyses statistically recalculate the data from the original studies based on standard criteria. The procedures for these calculations are beyond the scope of this book.
Research Workshop 3.1 Writing the literature review
There are different ways of organizing your literature review, but one simple way to get you started may initiate from the table where all your literature is mapped out along with your annotated bibliography. Taking these simple steps may give you some ideas on how to write a solid literature review:
1. Look out for things that are similar to or different from all (or most) of the articles.
Anything from the types of methodologies used to participants, use of theory, or findings. Sometimes the same theory is overused and you may be thinking that a different perspective may help this same topic. Other times all the participants may be from the same gender or the same ethnicity, and you may make the point that we need more diversity on the issue.
2. Write down three or four points that you notice that are either the same across all studies or different (if different, group them).
3. Organize your literature in paragraphs, first by thinking broadly to then a narrow focus—this focus is the argument why your study will be an important addition to the current literature and different from it.
4. Write each point in its own paragraph with very simple sentences first and then expand by adding information you may have already written in your annotated bibliography.
5. The very end of your literature review should have some argument why your study is important to the scientific knowledge in this topic and how it will be different.
6. You may end by stating your own research question or hypotheses—but those can also be in their own section right after the literature review.
Summary
Writing a literature review is a rewarding task with added perks, such as (1) painting a picture on what the scientific literature in your topic really looks like; (2) pulling out studies that are relevant to your topic and showing your organizational skills in making sense of them; (3) displaying your creativity in designing the literature review that best supports and complements your study; (4) exercising critical thinking by looking at the
studies from various perspectives; and (5) writing a logical, critical, and analytical literature review that supports your proposed study and naturally ends with your research question(s) or hypotheses.
In this chapter, you were introduced to some helpful tips on how to organize the literature and, most importantly, how to initially conceptualize the tasks. This organization is unique to each researcher, but some helpful tips were provided in how to look for patterns, similarities in methodologies or findings, as well as distinctive differences or opposing results from studies. Your literature review will culminate with the hypotheses or research questions you have formulated. For every alternative hypothesis, we include a null hypothesis because the null hypothesis is the one we will eventually try to reject.
This chapter also introduced systematic reviews of literature and how they are different from the traditional literature reviews. A systematic review of literature tends to be protected from selection biases—biases related to how we choose studies to include in our review. A systematic review also follows rigorous steps and procedures compared to the traditional review. After all, a systematic review of literature is best conceptualized as a research design rather than a literature review. It usually has its own traditional
literature review. Systematic reviews are also more organized and full of details on the studies they have investigated. This allows researchers to paint a complete picture on the literature of a specific topic. Meta-analyses are similar to systematic reviews with an added feature of statistically recalculating the data from original studies.
Key Terms
Annotated bibliography: a brief summary of the article or book you read, including the focus of the study, the methodology used, the findings, and any other important information that directly relates to your research topic.
Boolean operators: operators that are used to conduct searches in the library and other databases (i.e., AND, OR, NOT).
Interlibrary loan: the possibility of borrowing articles and books from other libraries that may not be available in your local or university library.
Literature review: the body of literature surrounding a specific topic of interest to the researcher.
Meta-analyses: the type of systematic reviews that statistically
recalculate the data from the original studies based on standard criteria.
Meta-analyses are a rigorous way of conducting systematic reviews.
Methodology of the systematic reviews: answers the question about how the articles and books (and other media) included in the
systematic review were collected, what keywords were used, what techniques were used to narrow down the number of published
records, and what rules were followed for selecting the final sample of articles and books.
Selection bias: biases that surround the way we select and decide which articles to use for our literature review. To avoid selection bias, we often conduct a systematic review of the literature on the topic.
Systematic review: a review of the literature that follows specific guidelines in collecting studies on a topic. It is usually less prone to biases.