Scientific Method

The scientific method is a range of techniques for investigating particular phenomena, acquiring new scientific knowledge, or correcting and integrating previous scientific knowledge. To be classified as scientific, a method of investigation is commonly based on empirical or measurable evidence and is subject to specific reasoning processes.

The reasoning process of the scientific method includes;


An observation is an unbiased accurate report of an event. Observations can be made directly using our senses (seeing, hearing etc.), or indirectly using equipment e.g. thermometers or microscopes. For example, a cancer biologist might notice that a particular type of cancer cannot be treated with chemotherapy and be curious why this is the case. Similarly, a marine ecologist, observing that coral reefs of her study sites are bleaching might seek to understand why.

Hypothesis testing

A hypothesis is a suggested explanation of a phenomenon, or alternatively a reasoned proposal suggesting a possible relationship between or among a set of phenomena. The hypothesis must be testable and falsifiable. Falsifiable means that there must be a possible negative answer to the hypothesis. Scientists can use whatever resources they have available - e.g. their own creativity or ideas from other research fields - to develop possible explanations for a hypothesis under study. A useful hypothesis will enable an individual to generate predictions of the results of the future experiment. For instance, it might predict the outcome of an experiment in a laboratory or the observation of a phenomenon in nature.

It is essential that the outcome of testing a hypothesis be currently unknown. Only then does a successful outcome increase the probability that the hypothesis is true. If the outcome is known prior to developing the hypothesis, it is called a consequence and should have already been considered while formulating the hypothesis.

Designing the Experiment

An experiment is subsequently designed to test a hypothesis and either prove or disprove predictions made during hypothesis development. If the experimental results confirm the predictions made during hypothesis testing, then the hypothesis is considered more likely to be correct, but might still be incorrect and continue to be subject to further testing. If the test results contradict those predictions made during hypothesis testing, the hypothesis can be questioned and it becomes less certain.

Occasionally, experiments are conducted incorrectly or are poorly designed, which can give incorrect results. Experimental control is a technique for dealing with these errors. This technique involves conducting experiments across multiple samples (or observations) under differing conditions to see what varies or what remains the same to contrast results. In such instances, conditions for each measurement are varied to help isolate what has changed.

Scientists assume an attitude of openness and accountability on the part of those conducting an experiment. Detailed record keeping is essential, to aid in recording and reporting on the experimental results, and supports the effectiveness and integrity of the procedure. They will also assist in reproducing the experimental results by others.

Collecting and Interpreting data

Data generated during the experiment (measurements, observations or information) are collected and analysed. Because it is often difficult to examine all the data, data are instead generally gathered from a smaller unit, or a subset of the population referred to as a sample. Data from the sample are used to predict (or infer) what the characteristics of the population as a whole may be e.g. a cancer biologist examining why a particular cancer cannot be treated with chemotherapy might ask a specified number of cancer patients to partake in her study (sample) rather than asking all cancer patients nationally to partake (population).

A common method of analysing numerical data is statistical analysis. This can include the use of graphs and tables to present the data in the most logical manner possible. Once the data has been analysed, it is subsequently available for interpretation to examine if the hypothesis is true or false.

Relating Conclusions to Existing Knowledge

Following interpretation of experiment results, the hypothesis can be confirmed, rejected or changed. If the hypothesis is confirmed, further testing with new experiments or observations can be conducted. However, this requires consistent and accurate results. If the hypothesis is unconfirmed/rejected, it can be changed and re-tested. Equally, these results can be compared with studies to either advance existing knowledge or develop new knowledge within a research area.

Publishing Findings

Once conclusions from the research have been identified, scientists should report their results so that experiments can be repeated by others. Results can be analysed and ideas published for all scientists. This contributes to the advancement of scientific understanding and knowledge.

Scientific journals are widely used to publish findings. Publishing in journals is subject to a process of peer review, in which scientists' manuscripts are submitted to the journal and then reviewed by two-four (usually anonymous) scientists familiar with the field. This standard is practice for scientists when publishing results, and keeps the scientific literature free of obvious errors and generally improve the quality of research. Research can also be published in magazines, newspapers, the Internet and TV.

Developing Theory

A theory is a hypothesis supported by numerous experiments and can be developed once the findings have been published to provide a comprehensive explanation of a particular phenomena. e.g. Darwinism is a theory of biological evolution developed by Charles Darwin and others, stating that all species of organisms arise and develop through the natural selection of small, inherited variations that increase the individual's ability to compete, survive, and reproduce.

Principles of Law

A law is a definite, factual explanation of an important aspect of nature e.g. a primary law of biology is that all living organisms consist of membrane-encased cells.

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