Interrupted time series analysis (ITS), sometimes known as quasi-experimental time series analysis, is a method of

statistical analysis Statistical inference is the process of using data analysis to infer properties of an underlying probability distribution.Upton, G., Cook, I. (2008) ''Oxford Dictionary of Statistics'', OUP. . Inferential statistical analysis infers properties of ...

involving tracking a long-term period before and after a point of intervention to assess the intervention's effects. The

time series In mathematics, a time series is a series of data points indexed (or listed or graphed) in time order. Most commonly, a time series is a sequence taken at successive equally spaced points in time. Thus it is a sequence of discrete-time data. ...

refers to the data over the period, while the interruption is the intervention, which is a controlled external influence or set of influences. Effects of the intervention are evaluated by changes in the level and slope of the time series and

statistical significance In statistical hypothesis testing, a result has statistical significance when a result at least as "extreme" would be very infrequent if the null hypothesis were true. More precisely, a study's defined significance level, denoted by \alpha, is the ...

of the intervention parameters. Interrupted time series design is the

design of experiments The design of experiments (DOE), also known as experiment design or experimental design, is the design of any task that aims to describe and explain the variation of information under conditions that are hypothesized to reflect the variation. ...

based on the interrupted time series approach. The method is used in various areas of research, such as: *

political science Political science is the scientific study of politics. It is a social science dealing with systems of governance and Power (social and political), power, and the analysis of political activities, political philosophy, political thought, polit ...

: impact of changes in laws on the behavior of people; (e.g., Effectiveness of sex offender registration policies in the United States) *

economics Economics () is a behavioral science that studies the Production (economics), production, distribution (economics), distribution, and Consumption (economics), consumption of goods and services. Economics focuses on the behaviour and interac ...

: impact of changes in credit controls on borrowing behavior; *

sociology Sociology is the scientific study of human society that focuses on society, human social behavior, patterns of Interpersonal ties, social relationships, social interaction, and aspects of culture associated with everyday life. The term sociol ...

: impact of experiments in income maintenance on the behavior of participants in

welfare program Welfare spending is a type of government support intended to ensure that members of a society can meet basic human needs such as food and shelter. Social security may either be synonymous with welfare, or refer specifically to social insurance pr ...

s; *

history History is the systematic study of the past, focusing primarily on the Human history, human past. As an academic discipline, it analyses and interprets evidence to construct narratives about what happened and explain why it happened. Some t ...

: impact of major historical events on the behavior of those affected by the events; *

psychology Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both consciousness, conscious and Unconscious mind, unconscious phenomena, and mental processes such as thoughts, feel ...

: impact of expressing emotional experiences on online content; *

medicine Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

: in medical research,

medical treatment A therapy or medical treatment is the attempted remediation of a health problem, usually following a medical diagnosis. Both words, ''treatment'' and ''therapy'', are often abbreviated tx, Tx, or Tx. As a rule, each therapy has indications an ...

is an intervention whose effect are to be studied; *

marketing research Marketing research is the systematic gathering, recording, and analysis of qualitative data, qualitative and quantitative data, quantitative data about issues relating to marketing products and services. The goal is to identify and assess how chan ...

: to analyze the effect of "designed market interventions" (e.g.,

advertising Advertising is the practice and techniques employed to bring attention to a Product (business), product or Service (economics), service. Advertising aims to present a product or service in terms of utility, advantages, and qualities of int ...

) on sales. * environmental sciences: impacts of human activities on environmental quality and ecosystem dynamics (e.g., forest logging on local climate).

References

Time series Quantitative research Design of experiments {{statistics-stub

See also

References