An important part of learning any science is having a basic knowledge of the techniques used in gathering information. The hallmark of scientific investigation is that of following a set of procedures designed to keep questioning or skepticism alive while describing, explaining, or testing any phenomenon. Some people are hesitant to trust academicians or researchers because they always seem to change their story. That, however, is exactly what science is all about; it involves continuously renewing our understanding of the subjects in question and an ongoing investigation of how and why events occur. Science is a vehicle for going on a never-ending journey. In the area of development, we have seen changes in recommendations for nutrition, in explanations of psychological states as people age, and in parenting advice. So think of learning about human development as a lifelong endeavor.

Take a moment to write down two things that you know about childhood. Now, how do you know? Chances are you know these things based on your own history (experiential reality) or based on what others have told you or cultural ideas (agreement reality) (Seccombe and Warner, 2004). There are several problems with personal inquiry. Read the following sentence aloud:

Paris in the

the spring

Are you sure that is what it said? Read it again:

Paris in the

the spring

If you read it differently the second time (adding the second “the”) you just experienced one of the problems with personal inquiry; that is, the tendency to see what we believe. Our assumptions very often guide our perceptions, consequently, when we believe something, we tend to see it even if it is not there. This problem may just be a result of cognitive ‘blinders’ or it may be part of a more conscious attempt to support our own views. Confirmation bias is the tendency to look for evidence that we are right and in so doing, we ignore contradictory evidence. Popper suggests that the distinction between that which is scientific and that which is unscientific is that science is falsifiable; scientific inquiry involves attempts to reject or refute a theory or set of assumptions (Thornton, 2005). Theory that cannot be falsified is not scientific. And much of what we do in personal inquiry involves drawing conclusions based on what we have personally experienced or validating our own experience by discussing what we think is true with others who share the same views.

Science offers a more systematic way to make comparisons guard against bias.

Scientific Methods

One method of scientific investigation involves the following steps:

  1. Determining a research question
  2. Reviewing previous studies addressing the topic in question (known as a literature review)
  3. Determining a method of gathering information
  4. Conducting the study
  5. Interpreting results
  6. Drawing conclusions; stating limitations of the study and suggestions for future research
  7. Making your findings available to others (both to share information and to have your work scrutinized by others)

Your findings can then be used by others as they explore the area of interest and through this process a literature or knowledge base is established. This model of scientific investigation presents research as a linear process guided by a specific research question. And it typically involves quantifying or using statistics to understand and report what has been studied. Many academic journals publish reports on studies conducted in this manner.

Another model of research referred to as qualitative research may involve steps such as these:

  1. Begin with a broad area of interest
  2. Gain entrance into a group to be researched
  3. Gather field notes about the setting, the people, the structure, the activities or other areas of interest
  4. Ask open ended, broad “grand tour” types of questions when interviewing subjects
  5. Modify research questions as study continues
  6. Note patterns or consistencies
  7. Explore new areas deemed important by the people being observed
  8. Report findings

In this type of research, theoretical ideas are “grounded” in the experiences of the participants. The researcher is the student and the people in the setting are the teachers as they inform the researcher of their world (Glazer & Strauss, 1967). Researchers are to be aware of their own biases and assumptions, acknowledge them and bracket them in efforts to keep them from limiting accuracy in reporting. Sometimes qualitative studies are used initially to explore a topic and more quantitative studies are used to test or explain what was first described.

Research Methods

Let’s look more closely at some techniques, or research methods, used to describe, explain, or evaluate. Each of these designs has strengths and weaknesses and is sometimes used in combination with other designs within a single study.

Observational Studies

Observational studies involve watching and recording the actions of participants. This may take place in the natural setting, such as observing children at play at a park, or behind a one-way glass while children are at play in a laboratory playroom. The researcher may follow a checklist and record the frequency and duration of events (perhaps how many conflicts occur among 2-year-olds) or may observe and record as much as possible about an event (such as observing children in a classroom and capturing the details about the room design and what the children and teachers are doing and saying). In general, observational studies have the strength of allowing the researcher to see how people behave rather than relying on self-report. What people do and what they say they do are often very different. A major weakness of observational studies is that they do not allow the researcher to explain causal relationships. Yet, observational studies are useful and widely used when studying children. Children tend to change their behavior when they know they are being watched (known as the Hawthorne effect) and may not survey well.

Case Studies

Case studies involve exploring a single case or situation in great detail. Information may be gathered with the use of observation, interviews, testing, or other methods to uncover as much as possible about a person or situation. Case studies are helpful when investigating unusual situations such as brain trauma or children reared in isolation. And they are often used by clinicians who conduct case studies as part of their normal practice when gathering information about a client or patient coming in for treatment. Case studies can be used to explore areas about which little is known and can provide rich detail about situations or conditions. However, the findings from case studies cannot be generalized or applied to larger populations; this is because cases are not randomly selected and no control group is used for comparison.

Figure 1.7
Illustrated poster from a classroom describing a case study.12

Surveys

Surveys are familiar to most people because they are so widely used. Surveys enhance accessibility to subjects because they can be conducted in person, over the phone, through the mail, or online. A survey involves asking a standard set of questions to a group of subjects. In a highly structured survey, subjects are forced to choose from a response set such as “strongly disagree, disagree, undecided, agree, strongly agree”; or “0, 1-5, 6-10, etc.” This is known as Likert Scale. Surveys are commonly used by sociologists, marketing researchers, political scientists, therapists, and others to gather information on many variables in a relatively short period of time. Surveys typically yield surface information on a wide variety of factors, but may not allow for in-depth understanding of human behavior.

Of course, surveys can be designed in a number of ways. They may include forced choice questions and semi-structured questions in which the researcher allows the respondent to describe or give details about certain events. One of the most difficult aspects of designing a good survey is wording questions in an unbiased way and asking the right questions so that respondents can give a clear response rather than choosing “undecided” each time. Knowing that 30% of respondents are undecided is of little use! So a lot of time and effort should be placed on the construction of survey items. One of the benefits of having forced choice items is that each response is coded so that the results can be quickly entered and analyzed using statistical software. Analysis takes much longer when respondents give lengthy responses that must be analyzed in a different way. Surveys are useful in examining stated values, attitudes, opinions, and reporting on practices. However, they are based on self-report or what people say they do rather than on observation and this can limit accuracy.

Experiments

Experiments are designed to test hypotheses (or specific statements about the relationship between variables) in a controlled setting in efforts to explain how certain factors or events produce outcomes. A variable is anything that changes in value. Concepts are operationalized or transformed into variables in research, which means that the researcher must specify exactly what is going to be measured in the study.

Three conditions must be met in order to establish cause and effect. Experimental designs are useful in meeting these conditions.

First, the independent and dependent variables must be related. In other words, when one is altered, the other changes in response. (The independent variable is something altered or introduced by the researcher. The dependent variable is the outcome or the factor affected by the introduction of the independent variable. For example, if we are looking at the impact of exercise on stress levels, the independent variable would be exercise; the dependent variable would be stress.)

Second, the cause must come before the effect. Experiments involve measuring subjects on the dependent variable before exposing them to the independent variable (establishing a baseline). So we would measure the subjects’ level of stress before introducing exercise and then again after the exercise to see if there has been a change in stress levels. (Observational and survey research does not always allow us to look at the timing of these events, which makes understanding causality problematic with these designs.)

Third, the cause must be isolated. The researcher must ensure that no outside, perhaps unknown variables are actually causing the effect we see. The experimental design helps make this possible. In an experiment, we would make sure that our subjects’ diets were held constant throughout the exercise program. Otherwise, diet might really be creating the change in stress level rather than exercise.

A basic experimental design involves beginning with a sample (or subset of a population) and randomly assigning subjects to one of two groups: the experimental group or the control group. The experimental group is the group that is going to be exposed to an independent variable or condition the researcher is introducing as a potential cause of an event. The control group is going to be used for comparison and is going to have the same experience as the experimental group but will not be exposed to the independent variable. After exposing the experimental group to the independent variable, the two groups are measured again to see if a change has occurred. If so, we are in a better position to suggest that the independent variable caused the change in the dependent variable.

The major advantage of the experimental design is that of helping to establish cause and effect relationships. A disadvantage of this design is the difficulty of translating much of what happens in a laboratory setting into real life.

Example

Imagine that you want to know if exercise during pregnancy has an impact on newborn’s breathing and sleeping patterns. In this case, exercise is your independent variable because that’s what you will be manipulating (i.e., changing). You recruit 100 participants. In this case all of your participants would be pregnant and not currently exercising. You randomly assign them to your groups; 50 participants end up in the control group and 50 participants end up in the experimental group. The control group is simply there for comparison, so you want to keep their experience as close to normal as possible. In this case, they would NOT engage in any exercise; they would just continue with their lives as normal. The experimental group would begin an exercise program designed for the study (for example, walking for 30 minutes three times a week). You would then wait for your participants to give birth to their babies and would then take measures of breathing and sleeping patterns in the newborns. Breathing and sleeping patterns are your dependent variables, the outcomes you are measuring. Based on this set up, you could ask and answer the question: does exercising during pregnancy cause a significant change in newborn’s breathing and sleeping patterns? Or: were the breathing and sleeping patterns of the newborns significantly different between those born to participants in my control group versus my experimental group? If there is a difference, you could say that exercise during pregnancy caused that difference.

Developmental Designs

Developmental designs are techniques used in developmental research (and other areas as well). These techniques try to examine how age, cohort, gender, and social class impact development.

Longitudinal Research

Longitudinal research involves beginning with a group of people who may be of the same age and background, and measuring them repeatedly over a long period of time. One of the benefits of this type of research is that people can be followed through time and be compared with them when they were younger.

Flowchart with four boxes depicting the same child being studied every two years from ages 2 to 8
A longitudinal research design.13

A problem with this type of research is that it is very expensive and subjects may drop out over time. The Perry Preschool Project which began in 1962 is an example of a longitudinal study that has provided data on children’s development.

Cross-sectional Research

Cross-sectional research involves beginning with a sample that represents a cross-section of the population. Respondents who vary in age, gender, ethnicity, and social class might be asked to complete a survey about television program preferences or attitudes toward the use of the Internet. The attitudes of males and females could then be compared, as could attitudes based on age. In cross-sectional research, respondents are measured only once.

Diagram showing three groups of people all being studied in the same year. One group of 2 year olds, one group of 6 year olds, and one group of 8 year olds.
A cross-sectional research design.14

This method is much less expensive than longitudinal research but does not allow the researcher to distinguish between the impact of age and cohort effects. Cohort effects refer to characteristics due to a person’s time of birth, era, and generation but not to actual age. Different attitudes about the use of technology, for example, might not be altered by a person’s biological age as much as their life experiences as members of a cohort.

Sequential Research

Sequential research involves combining aspects of the previous two techniques; beginning with a cross-sectional sample and measuring them through time.

Diagram depicting the combination of a longitudinal and cross-sectional research design.
A sequential research design.15

 

Advantages and Disadvantages of Different Research Designs17

Type of Research Design

Advantages

Disadvantages

Longitudinal

  • Examines changes within individuals over time
  • Provides a developmental analysis
  • Expensive
  • Takes a long time
  • Participant attrition
  • Possibility of practice effects
  • Cannot examine cohort effects

Cross-sectional

  • Examines changes between participants of different ages at the same point in time
  • Provides information on age-related change
  • Cannot examine change over time
  • Cannot examine cohort effects

Sequential

  • Examines changes within individuals over time
  • Examines changes between participants of different ages at the same point in time
  • Can be used to examine cohort effects
  • May be expensive
  • Possibility of practice effects

Consent and Ethics in Research

Research should, as much as possible, be based on participants’ freely volunteered informed consent. For minors, this also requires consent from their legal guardians. This implies a responsibility to explain fully and meaningfully to both the child and their guardians what the research is about and how it will be disseminated. Participants and their legal guardians should be aware of the research purpose and procedures, their right to refuse to participate; the extent to which confidentiality will be maintained; the potential uses to which the data might be put; the foreseeable risks and expected benefits; and that participants have the right to discontinue at any time.

But consent alone does not absolve the responsibility of researchers to anticipate and guard against potential harmful consequences for participants.18 It is critical that researchers protect all rights of the participants including confidentiality.

Child development is a fascinating field of study – but care must be taken to ensure that researchers use appropriate methods to examine infant and child behavior, use the correct experimental design to answer their questions, and be aware of the special challenges that are part-and-parcel of developmental research. Hopefully, this information helped you develop an understanding of these various issues and to be ready to think more critically about research questions that interest you. There are so many interesting questions that remain to be examined by future generations of developmental scientists – maybe you will make one of the next big discoveries!19


Attributions

12 Image by MaryGeorge is licensed under CC BY-SA 4.0
13 Image by NOBA is licensed under CC BY-NC-SA 4.0
14 Image by NOBA is licensed under CC BY-NC-SA 4.0
15 Image by NOBA is licensed under CC BY-NC-SA 4.0
16 Research Methods by Lumen Learning is licensed under CC BY 4.0
17 Research Methods in Developmental Psychology by Angela Lukowski and Helen Milojevich is licensed under a CC BY-NC-SA 4.0
18 Confidentiality and Informed Consent: Issues for Consideration in the Preservation of and Provision of Access to Qualitative Data Archives by Louise Corti, Annette Day & Gill BackhouseSource is licensed under CC BY 4.0 (modified by Jennifer Paris); “No thank you, not today”: Supporting Ethical and Professional Relationships in Large Qualitative Studies by Lisa J. Blodgett, Wanda Boyer & Emily TurkSource is licensed under CC BY 4.0 (modified by Jennifer Paris)
19 Research Methods in Developmental Psychology by Angela Lukowski and Helen Milojevich is licensed under a CC BY-NC-SA 4.0

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