There is no doubt that the scientific method illuminates and illustrates human development as nothing else does. Facts, hypotheses, and possibilities have all emerged that would not be known without science—
For example, infectious diseases in children, illiteracy in adults, depression in late adulthood, and racism and sexism at every age are much less prevalent today than a century ago. Science deserves credit for all these advances. Even violent death is less likely, with scientific discoveries and education likely reasons (Pinker, 2011).
Developmental scientists have also discovered unexpected sources of harm. Video games, cigarettes, television, shift work, and asbestos are all less benign than people first thought.
Although the benefits of science are many, so are the pitfalls. We now discuss three potential hazards: misinterpreting correlation, depending too heavily on numbers, and ignoring ethics.
Probably the most common mistake in interpreting research is the confusion of correlation with causation. A correlation exists between two variables if one variable is more (or less) likely to occur when the other does. Thus, there is a relationship or link between one variable and the other. A correlation is positive if both variables tend to increase together or decrease together, negative if one variable tends to increase while the other decreases, and zero if no connection is evident.
To illustrate: From birth to age 9, there is a positive correlation between age and height (children grow taller as they grow older), a negative correlation between age and amount of sleep (children sleep less as they grow older), and zero correlation between age and number of toes (children do not have more or fewer toes as they grow older). (Now try taking the quiz on correlation in TABLE 1.7.)
Two Variables | Positive, Negative, or Zero Correlation? | Why? (Third Variable) |
---|---|---|
1. Ice cream sales and murder rate | ____________ | ____________ |
2. Learning to read and number of baby teeth | ____________ | ____________ |
3. Child gender and sex of parent | ____________ | ____________ |
For each of these three pairs of variables, indicate whether the correlation between them is positive, negative, or non- |
Expressed in numerical terms, correlations vary from +1.0 (the most positive) to –1.0 (the most negative). Correlations are almost never that extreme; a correlation of +0.3 or –0.3 is noteworthy; a correlation of +0.8 or –0.8 is astonishing.
Many correlations are unexpected. For instance, first-
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A second caution concerns how heavily scientists should rely on data produced by quantitative research (from the word quantity). Quantitative research data can be categorized, ranked, or numbered and thus can be easily translated across cultures and for diverse populations. One example of quantitative research is the use of children’s school achievement scores to measure the effectiveness of education.
Since quantities can be easily summarized, compared, charted, and replicated, many scientists prefer quantitative research. Statistics require numbers. Quantitative data are easier to replicate and less open to bias, although researchers who choose this method have some implicit beliefs about evidence and verification (Creswell, 2009).
When data are presented in categories and numbers, some nuances and individual distinctions are lost. Many developmental researchers thus turn to qualitative research (from quality)—asking open-
Developmentalists use both quantitative and qualitative methods (Creswell, 2009). Sometimes they translate qualitative research into quantifiable data; sometimes they use qualitative studies to suggest hypotheses for quantitative research.
ESPECIALLY FOR People Who Have Applied to College, University, or Graduate School Is the admissions process based on quality or quantity?
One caution applies especially to qualitative research: Scientists must not leap to conclusions on the basis of one small study. In the same way, personal experiences may suggest topics and hypotheses, but the particulars of our lives are no substitute for empirical research on hundreds of other people. Another caution applies to quantitative research: The accuracy of the conclusions depends on exactly how the numbers were defined and collected—
The most important caution for all scientists, especially for those studying humans, is to uphold ethical standards in their research. Each academic discipline and professional society involved in the study of human development has a code of ethics (a set of moral principles) and specific practices within a scientific culture to protect the integrity of research and research participants.
Ethical standards and codes are increasingly stringent. In Canada, most educational and medical institutions have a Research Ethics Board (REB), a group that permits only research that follows certain guidelines. Although REBs often slow down scientific study, some research conducted before they were established was clearly unethical, especially when the participants were children, members of minority groups, prisoners, or animals (Blum, 2002; Washington, 2006).
Protection of Research ParticipantsResearchers must ensure that participation is voluntary, confidential, and harmless. In Western nations, this entails the informed consent of the participants—
If children are involved, consent must be obtained from the parents as well as the children, and the children must be allowed to end their participation at any time. In some other nations, ethical standards require consent of the village elders and heads of families, in addition to that of the research participants themselves (Doumbo, 2005).
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Historically, shocking examples of unethical practices—
ESPECIALLY FOR Future Researchers and Science Writers Do any ethical guidelines apply when an author writes about the experiences of family members, friends, or research participants?
Protection of participants may conflict with the goals of science. The Canadian Psychological Association suggests ways to resolve this conflict. Its four guiding principles are
Note that all four of these principles should be followed, if possible, but they are ranked in order of importance: Respect for individuals is most important (Canadian Psychological Association, 2010).
Implications of Research ResultsOnce a study has been completed, additional issues arise. Scientists are obligated to promote “accuracy, honesty, and the obvious prohibitions of fraud or misrepresentation” (Canadian Psychological Association, 2000).
Deliberate falsification is rare. When it does occur, it leads to ostracism from the scientific community, dismissal from a teaching or research position, and, sometimes, criminal prosecution. Another obvious breach of ethics is to “cook” the data, or distort one’s findings, in order to make a particular conclusion seem to be the only reasonable one. This is not as rare as it should be. Tenure, promotion, and funding all encourage scientists to publish, and publishers to seek, remarkable findings. Researchers recognize the “file-
Insidious dangers include unintentionally slanting the conclusions and withholding publication of a result, especially when there is “ferocious…pressure from commercial funders to ignore good scientific practice” (Bateson, 2005). Similarly, non-
Ethical standards cannot be taken for granted. As stressed at the beginning of this chapter, researchers, like all other humans, have strong opinions, which they expect research to confirm. Therefore, they might try (sometimes without even realizing it) to achieve the results they want. One team explains:
Our job as scientists is to discover truths about the world. We generate hypotheses, collect data, and examine whether or not the data are consistent with those hypotheses…[but we] often lose sight of this goal, yielding to pressure to do whatever is justifiable to compile a set of studies we can publish. This is not driven by a willingness to deceive but by the self-
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[Simmons et al., 2011, pp. 1359 & 1365]
Obviously, collaboration, replication, and transparency are essential ethical safeguards for all scientists.
Finally, the most important ethical concern for developmentalists is to study issues that will help “all kinds of people, everywhere, of every age” live satisfying and productive lives. Consider these questions, for instance:
The answer to all these questions is a resounding NO. The reasons are many, but a major one is that these topics are controversial. Some researchers avoid them, fearing unwelcome and uninformed publicity (Kempner et al., 2005). Few funders are eager to support scientific studies of drug abuse, poverty, non-
The next cohort of developmental scientists will build on what is known, mindful of what needs to be explored. Remember that the goal is to help all 7 billion people on Earth fulfill their potential. Much more needs to be learned. This book is only a beginning.
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