Science and The Scientific Method
Science is the pursuit of systemized knowledge through observation.
The term comes from the Latin word ‘scire’ meaning, “to know,” refers to
both a method and a goal.
It is important for scientific observations and explanations to be testable and
Testability and Replicability
A scientific approach requires that propositions and ideas be stated in a clear
and precise way.
Statements, theories, and assertions must be testable in the public arena and
subject to disproof.
Closely related to testability is the requirement that each observation that
contributes to scientific body of knowledge be replicable or reliable. It must
occur under prescribed circumstances not once, but repeatedly.
The Role of Theory
A theory is a set of propositions meant to explain a class of phenomena.
The primary goal of science is to advance theories to account for data, often
by proposing cause – effect relationships.
Empirical research allows the adequacy of theories to be evaluated.
A theory permits the generation of hypothesis-expectations about what
should occur if a theory is true.
The generation of a theory asserts that a scientist formulates a theory by
simply considering data that has been previously collected and then deciding,
and a rather straightforward fashion, is a given way of thinking about the
data is the most economical and useful.
Theories are constructions put together by scientists.
Scientists must often make use of theoretical concepts: unobservable states
or processes that are inferred from observable data.
Theoretical concepts can also summarize already observed relationships.
Operationism: school of thought that proposes that each concept takes its
meaning a single observable and measurable operation. Each theoretical
concept would be nothing more than one particular measurable. In this way,
its generality is lost.
The early operation's point of view quickly gave way to more flexible
position that a theoretical concept can be defined by sets of operations or
The Research Methods of Abnormal Psychology
The Case Study
A case study collects historical and biographical information on a single
individual, often including experiences during therapy sessions.
A case study would cover family history and background, medical history,
educational background, jobs held, marital history, and details concerning
development, adjustment and personality, life course, and current situations.
Providing Detailed Description The validity of the information gathered in the case study is sometimes
Constant comparative method: identification of relevant units of information,
placing the units into categories that emerge from the data and providing
organizational teams for the information.
The Case Study as Evidence
Case histories are especially useful when they negate an assumed universal
relationship or law.
Case studies do not provide the means for ruling out alternative hypothesis.
Through exposure to life histories of a great number of clients, clinicians may
notice similarities of circumstances and formulate hypothesis that could not
have been uncovered in a more controlled investigation.
The case study is an excellent way of examining the behavior of a single
individual in great detail and generating hypothesis that can later be
evaluated by controlled research.
But when general, universal laws are sought to explain phenomena, the case
study is of limited use.
Epidemiology is the study of the frequency and distribution of the disorder in
This information can be used to give a general picture of the disorder, how
many people it affects, whether it is more common in men than in women
and whether its occurrence also varies according to social and cultural
Epidemiological research focuses on three features of a disorder:
1. Prevalence: the proportion of a population that has the disorder at the given
point or period of time
2. Incidence: the number of new cases of the disorder that occur in some
period, usually within a year
3. Risk factors: conditions are variables thought, if present, increase the
likelihood of developing the disorder
Epidemiology is important for planning healthcare facilities and services and
for allocating provincial and federal grants for the study of disorders.
The Correlational Method
Correlational method establishes whether there is a relationship between or
among two or more variables.
The variables being studied are measured, as they exist in nature.
The first step in determining a correlation is to obtain pairs of observations
of the variables in question, such as height and weight, for each member of
the group of participants.
The strength of the relationship between two sets of observations can be
calculated to determine the correlation coefficient. The relationship is
represented by r. If r is positive, it is, the two variables are said to be positively related. If r is negative, the two variables are said to be negatively
In perfect relationships, all the points on the straight line.
Statistical significance refers to the likelihood that the results of an
investigation are due to chance.
A statistically significant correlation is one that is not likely to have occurred
Traditionally, and psychological research, a correlation is considered
statistically significant if the likelihood or probability that it is a chance
finding is five or less in 100, commonly written as p=.05.
As the size of the correlation coefficient increases, the result is more and
more likely to be statistically significant.
When a correlation attains statistical significance also depends on the
number of observations made. The greater the number of observations, the
smaller r (the correlation) needs to be to reach statistical significance.
Applications to Psychopathology
When the correlational method is used in research and psychopathology, one
of the variables is typically diagnosis; for example, whether the participant is