手法を比較

	縦断的定量的内容分析	記述的研究
分野	研究デザイン	研究デザイン
系統	Process / pipeline	Process / pipeline
提唱年	1950s onward; longitudinal application widely adopted in media research by the 1970s–1980s	Late 19th century; formalized in social/behavioral sciences ~1960s–1980s
提唱者	Developed within communication and media studies; codified by Berelson (1952) and extended by Riffe, Lacy, Fico	Francis Galton, Karl Pearson (early empirical tradition); formalized in social science by Fred Kerlinger
種類	Quantitative observational research design	Non-experimental quantitative research design
原典	Riffe, D., Lacy, S., Watson, B., & Fico, F. (2019). Analyzing Media Messages: Using Quantitative Content Analysis in Research (4th ed.). Routledge. ISBN: 9781138490536	Creswell, J. W. (2014). Research Design: Qualitative, Quantitative, and Mixed Methods Approaches (4th ed.). Sage. ISBN: 978-1452226101
別名	longitudinal content analysis, repeated-measure content analysis, time-series content analysis, longitudinal QCA	descriptive study, descriptive survey design, observational descriptive research, non-experimental descriptive research
関連	5	3
概要	Longitudinal quantitative content analysis systematically codes and counts features of texts, images, or media messages gathered at two or more points in time, enabling researchers to track how content changes, how themes rise or fall in prevalence, and how media or institutional messaging responds to external events. The design merges the structured measurement logic of quantitative content analysis with the temporal tracking power of longitudinal observation.	Descriptive research is a non-experimental quantitative design that systematically documents the characteristics, frequencies, or distributions of variables in a defined population at a given point in time. It answers 'what is' questions — who, what, when, where, and how much — without manipulating variables or drawing causal conclusions. It is one of the most widely used research designs across the social, behavioral, health, and education sciences.