If we say something is scientific, it doesn't actually make it scientific. The same can be said about psychology. Scientific processes have been established to ensure that research meets the expected standard.
- We will start by covering the scientific method: psychology.
- Then, we will delve into the scientific method steps.
- Moving on, we will explore the scientific method in research.
- Next, we will look at some scientific investigation examples commonly used in psychology.
- Finally, we will explore the scientific method experiments.
Scientific Method Psychology
The scientific process is an empirical method developed by Sir Francis Bacon, providing a framework for researchers to follow.
Empirical research is thus enabled, and biases that affect the interpretation of results are limited. We conduct empirical research by empirically testing falsifiable hypotheses and determining whether these predictions are consistent with previous empirical observations.
The term 'empirical' refers to a phenomenon or data that has been observed and measured in a carefully controlled manner (scientifically).
There are different requirements of scientific research:
- When conducting research with a scientific background, we must use vigorous, empirical methods through controlled experiments to arrive at results that we can apply to real-life settings, such as treating disease.
- Reliability – the procedure description should be detailed and easy for other researchers to replicate. Researchers can then examine its reliability and determine the generalisability of results; this is the case when similar findings are found.
- Validity – the scientific process provides researchers with an empirical technique that limits data bias, thus increasing validity.
There are different paradigms/schools of thought in psychology; essentially, these are the approaches of psychology.
Each approach explains human behaviour causes differently and has different preferences towards research methods.
Fig. 1. Scientific research should be empirical, reliable and valid.
Scientific Method Steps
The scientific process involves formulating hypotheses using inductive methods (e.g., collecting observations of natural phenomena) to develop a theory or research question.
We then make deductions from hypotheses based on the results of the experiment. We adjust or eliminate the hypotheses depending on whether the conclusions drawn are supportive or contradictory. Thus, the scientific process is also called a hypothetico-deductive model.
| Scientific Method Steps | Description |
| Observations and research questions | Initially, researchers observe natural phenomena. Researchers formulate research questions based on these observations to understand the research area better. |
| Formulating hypotheses | Based on the research questions, researchers need to formulate hypotheses.Hypotheses need to be predictive and falsifiable statements. They can be supported or negated via observations or experimental methods. |
| Testing hypothesis | Researchers must design and conduct experiments or observations that test the hypothesis.Experiment study designs must be verifiable, i.e. allow other researchers to replicate them. Such experiments guarantee the reliability of the results. For this, a detailed description of the procedural techniques is required. |
| Analysing data | The researcher carries out statistical tests to confirm or refute hypotheses. For quantifiable data, if the analysis is statistically significant data following the direction of the hypothesis, supportive evidence of the thesis is implied. And if insignificant findings and the results opposite of the hypothesis are found, the alternative hypothesis is rejected.Another critical factor is that all data must be reported according to APA guidelines, whether they support or reject the hypothesis. |
| Drawing conclusions | This stage involves drawing conclusions based on the data obtained and comparing it to previous literature. Previous findings that support or contradict the current research evidence summarise the research area. This section should answer the initial research question. If contradictory results appear, the researcher should refine and re-test the hypothesis following the stages of the scientific process. |
The scientific method steps follow a cycle. Once the conclusions are drawn, the researcher builds on what they have learned and follows the same steps to conduct their subsequent research.
When writing-up research, a scientific report must follow specific guidelines by the APA (American Psychological Association). Before it is accepted, the study and the report must be peer-reviewed.
Peer review is when established psychological researchers verify whether research should be accepted and published in a journal based on whether it meets the scientific research requirements.
For instance, empiricism, validity and reliability for quantitative research. Or transferability, credibility and confirmability for qualitative research).
Scientific Method in Research
Hypotheses are predictive statements composed of research findings that set expectations for the experiment. We usually deduce hypotheses from background research.
Hypotheses differ from aims in that they give a broad sense of the purpose of research.
There are different types of hypotheses in scientific research.
| Types of Alternative Hypothesis | Definition and Example |
| Directional Hypothesis | The researcher states what direction the results are expected to go, e.g. students who revised more will score higher in exams (%) than those who revised less. |
| Non-directional Hypothesis | The researcher states there will be a difference but doesn't state the direction of the expected results, e.g. students who used revision guide A will differ from exam scores (%) of students who used revision guide B. |
And a null hypothesis is when the researcher expects to find no difference between variables.
In scientific research, hypotheses must identify variables and operationalise these.
The two types of variables investigated in scientific research are independent variables (what the researcher manipulates and is theorised as the cause of a phenomenon) and dependent variables (what the researcher measures, theorised as the effect of a phenomenon).
Operationalised variables mean that the researcher should state the variable's unit of measurement and how these will be measured, e.g. if they use an established questionnaire or inventory.
Scientific Investigation Examples
There are scientific investigations; let's take a look at a few.
| Types of Scientific Investigations | Description |
| Pilot studies | These are preliminary research used to test out research before a full-blown experiment is conducted. The aim of pilot studies is to test and adapt research so that the research is in its best shape when conducted. A pilot study must be conducted when using new measures.For example, constructing questionnaires, e.g. creating new ones, must be piloted before being used in an experiment. |
| Experiments | Experiments are research conducted in controlled environments and involve manipulating and measuring variables of interest. Only from controlled, empirical, objective, valid and reliable experimental research can psychology researchers make causation inferences. |
| Observational design | The experiment involves watching (overt or covert) participants in different environments (controlled or naturalistic) participants and recording their behaviour to identify if the findings support or negate the proposed hypothesis. |
| Self-report design | This is when measures such as some types of interviews, psychometric tests or questionnaires are sent to respondents, i.e. a measure that involves respondents giving information without researcher interference. |
Scientific Method Experiments
Let's move our focus to scientific methods in experiments. There are several types of experiments used in psychology.
When conducting scientific method experiments, researchers must consider sampling techniques, experimental designs, and ethical issues when designing experimental research.
Experimental designs are how participants are divided into conditions/groups to manipulate the different independent variable levels (e.g. experimental and control groups).
And the sampling techniques are various methods used to allocate participants to the different experimental conditions.
The three experimental groups design used in psychology are:
- Independent Group Design (IGD) - Participants participate in one condition, e.g. one group receives CBT, and the other group receives medication.
- Repeated-Measures Design (RMD) - The same participants partake in each condition, e.g. researchers measure depression scores before and after an intervention.
- Matched Pairs Design (MPD) - Participants are matched based on key characteristics of interest, e.g. age or height. One of each pair will be assigned to the experimental group and the other to the control group.
Several sampling techniques, e.g. volunteer, opportunity, random, snowball, systematic, etc., can be used in psychological research.
Random sampling is considered the optimum sampling technique as it involves the least researcher involvement, so it is the least likely to be influenced by subjectivity and researcher bias. Researcher bias reduces the study's validity
The five main ethical issues in psychological research are as follows:
- Informed consent.
- Confidentiality.
- Prevent psychological/ physical harm.
- Deception.
- Rights to withdraw.
Scientific Processes - Key takeaways
- The scientific method: psychology suggests research should be empirical, reliable and valid.
- There are five scientific method steps: making observations and research questions, formulating hypotheses, testing the hypothesis, analysing the data and drawing conclusions from the data.
- The scientific method in research should identify aims and hypotheses, including operationalised variables.
- Some scientific investigation examples are pilot studies, experiments, observational designs and self-report techniques, to name a few.
- When conducting scientific method experiments, researchers must consider sampling techniques, experimental designs, and ethical issues when designing experimental research.
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