Types of question and types of variable Training session 4 GAP Toolkit 5 Training in basic drug abuse data management and analysis

Objectives Define a range of classifications for questions and variables Discuss the use of levels of measurement in defining variables in SPSS

Types of question Closed, open “Factual” and attitudinal

Closed questions The respondent selects from a list of mutually exclusive and collectively exhaustive answers The answers are pre-coded

Example Has the patient been in treatment prior to this episode?  Yes (1)  No (0)

Example In the last 30 days, how many times (if any) have you had 5 or more drinks in a row?  None  1  2  3-5  6-9  10 or more

“Other” Category An option on all but the simplest closed questions Ensures the list of options are exhaustive Allows flexibility in response Post-coded rather than pre-coded

Example Type of centre:  Specialized treatment centre  Therapeutic community  General hospital  Psychiatric hospital/unit  Other (specify): …………………………..

Dichotomous questions A subset of closed questions There are only two possible answers The answers are mutually exclusive and collectively exhaustive

Examples 1. Gender:  Male  Female 2. Has the patient been in treatment prior to this episode?  Yes  No

Multiple-response questions The question allows more than one response The categories are not mutually exclusive Frequently, a grouping of dichotomous closed questions

Example Mode of ingestion of primary substance (X all that apply):  Swallow  Smoke  Snort  Inject  Other (specify): ……………………………….

Likert Scales A type of closed question Designed to measure attitudes

Example Do you disapprove of people doing each of the following: –Trying marijuana once or twice  Don’t approve  Disapprove  Strongly disapprove  Don’t know –Smoking marijuana occasionally (options repeated)

Open questions There are no constraints on the respondent’s answer The answers cannot be predicted before the questionnaires are presented The answers must be coded after the questionnaires are collected

Examples 1.Q30. Which new drugs or new patterns of use have been reported? 2.Q13. Indicate primary substance of abuse, that is, the most frequently used 3.Other (specify): ……………………..

Exercise: discussion Do Open or Closed questions appear more frequently in the questionnaires used by your specific focal group? Give reasons/possible explanations for these choices.

Response types Factual/attitudinal Direct/indirect

Types of variable Levels of measurement Types of variation Categorical vs. continuous

Levels of measurement Nominal Ordinal Interval Ratio

Nominal The data describe an attribute The set of possible values the variable can contain are mutually exclusive and collectively exhaustive categories The categories cannot be objectively measured against each other

Examples: nominal data Gender: male and female Location: urban and rural Religion: Christian, Hindu, Muslim, Jew Race: white, black, coloured, mixed Referral source: self, employer, court

Ordinal The data are broken into categories that can be ranked It is not possible to quantify the difference between the categories

Example: ordinal Level of education:  None  Primary  Secondary  Tertiary

Interval The data are measured on a continuous scale, not simply ranked The units of measurement are constant There is no absolute 0

Example: interval Temperature: –Fahrenheit or Celsius Measured on a continuous scale No absolute 0

Ratio The data are measured on a continuous scale, not simply ranked The units of measurement are constant There is an absolute 0

Examples: ratio Age Income Temperature on the Kelvin Scale

Types of variation Nominal: equal categories Ordinal: ordered categories Interval and ratio: a continuous scale

Types of variation Qualitative: nominal Quantitative: interval and ratio Quantitative and qualitative: ordinal

Exercise: identify the levels of measurement Name of treatment centre Referral source Gender Age Home language Region of permanent residence Highest level of education completed Employment status Current marital status How old was the patient when they first began using drugs regularly?

Level of measurement in SPSS Nominal Ordinal Scale

Exercise: measure Return to Ex1.sav and set the level of measurement for the variables ID, DRUG, AGE and COND Save the file

Summary Question types: –Closed/Open –Factual/Attitudinal Variable types: –Levels of measurement –Discrete (categorical)/continuous –Quantitative/qualitative