Unit 10 – Statistics and Research (Ugghhh!!)

The Process Understanding statistics is research can be challenging When evaluating a research report, you should understand the following: The data collection process The data analyses used What the statistics mean

Data Collection and Preparation Data collection involves: Gathering data from study participants, commonly with a survey/questionnaire In qualitative research, surveys and questionnaires are used to collect data on participant characteristics (age, gender, ethnicity, etc.) Data preparation involves: Converting some of the data to codes (e.g. each of the 50 states coded 1-50) Entering codes into computer software Checking and handling missing data

Analyses Used in Nursing Research Analyses are used to: Describe data measures of central tendencies: mean, mode, median measures of dispersion: SD, range Make inferences about groups: Hypothesis testing Examine relationships between groups: Correlations Test differences between groups: T-tests, ANOVA Make predictions about populations: regression analyses

Things to Know about Data Analysis Descriptive statistics are used to summarize sample characteristics Significance of results: probability levels – p values.05 means that there is a 5/100 chance that outcome or relationship is the result of chance.01 means that there is a 1/100 chance that outcome or relationship is the result of chance P values less than.05 and less than.01 are statistically significant Correlations: r values The higher the correlation, the stronger the positive or negative correlation.3 = weak;.5 = moderate; >.5 = strong

Commonly Used Data Analyses in Nursing Statistical analysisStatisticInterpretation of significant results CorrelationCorrelation coefficient (r)Two variables are correlated t-testT statisticMeans of two groups are different Analysis of varianceF statistic Means of three or more groups are different Chi-squareχ 2 statisticThere is a difference between two groups on a selected variable

Example – Translation of Research Language to English Research Language English Twenty three patients were reached at the six-month telephone call and provided data on their smoking status (13 from the EG and 10 from the CG). The results indicated that 25% (5/20) of EG patients were non-smokers at six months compared to 30% (6/20) of CG patients (Chi-square 0.125, p = 0.72). Twenty three patients, 13 from a test group and 10 from a control group, were studied. The results indicated that 25% of the experimental group (EG) were non-smokers compared to 30% of control group (CG). The difference between the two groups was not significant.

When reading a research report, you should have a general idea of the statistics used and why they are being used

Critiquing a Research Report You are not expected to know how to conduct the statistical analysis but you should think about the following: If the appropriate statistics were used Is sample size adequate (were power analyses described) Are the results clearly displayed and described