PH 45 BEBEI SET

What is data management?

The entire process of record keeping before, during, and after a research study.

When does data management occur?

Before (planning), during (collection and entry), and after (cleaning, analysis, storage).

Core components of data management

Documentation (codebook), data entry, data cleaning, and data security.

Why is data management important?

Your analysis is only as good as your record keeping.

What is a codebook?

A "user manual" for the dataset that helps others understand and analyze it correctly.

What is data cleaning?

The process of correcting errors in data files.

Typographical errors in data

Mistakes like extra zeros, misplaced decimals, wrong category codes, or inconsistent spelling.

Out-of-range values

Values that are not possible or allowed (e.g., age = 5 in an adult sample).

Impossible combinations (logic errors)

Data patterns that cannot logically occur together (e.g., never used tobacco but reports smoking recently).

What is a derived variable?

A new variable created from existing variables during analysis.

What is recoding?

The process of creating a new variable based on one or more existing variables.

What do statistical software programs do?

Help organize, record, analyze, and visualize quantitative data.

What tasks can statistical software perform?

Run statistics and create graphs.

Common statistical software

R, Stata, SAS, SPSS.

Why are results from different programs similar?

They use the same underlying statistical methods.

SPSS tabs

Data View and Variable View.

Data View (SPSS)

Rows = participants; Columns = variables.

Variable View (SPSS)

Shows information about each variable.

What is a variable?

Any single item of information in a dataset.

Continuous variable

A numeric variable that can take any value within a range (e.g., weight).

Discrete variable

A numeric variable with specific, separate values (e.g., number of children).

Ordinal variable

A variable with a meaningful order (e.g., always → never).

Nominal variable

A categorical variable with no order (e.g., yes/no, hair color).