Translation and Cross- Cultural Equivalence of Health Measures
Feb 20, 2016
Translation and Cross-Cultural Equivalence of Health Measures
Context Multinational companies & international
drug trials Cross-cultural research within Canada International health studies General sense of globalization – but does
this downplay differences?
Relevance of Culture Culture shapes the way we conceive of health and
illness Influences customary behaviours, relationships
with others Influences relative values of symptoms Reactions to pain, etc. Expectations & definitions of feeling good, etc. ‘Questionnaire sophistication’ of the group
Level of abstraction Concepts can be:
Abstract and general Happiness, Ability
Concrete and specific Number of hospital beds per capita
More abstract concepts Applicable to different cultures, but
More imprecise Specific concepts
Less cross-culturally applicable More context dependent
Types of Cross-Cultural Equivalence
Is it operationalized in same way? (Same general measurement procedures)
Item equivalence: Items should mean the same thing to people in one culture as in another
Scalar equivalence (E.g., is the distance between “moderately severe” and “severe” the same in both cultures?)
Requirements for cross-cultural equivalence Conceptual/functional
Equivalence in construct operationalization
Item equivalence
Scalar equivalence
Hierarchical: must have first before second
Conceptual/FunctionalEquivalence
Is there a universal situation? Does construct mean the same thing in both
cultures? Can goal of behaviour be identified? Are same antecedent-consequent relations
demonstrable across cultures? Does same situation result in same behaviour
across cultures?
Equivalence in operationalization Is it operationalized in same way?
Same procedure
E.g. measuring disability with Questions on self-care
Measuring visual impairment with Snellen chart
Item equivalence Measured by same instrument
Items should mean the same thing to people in one culture as in another
E.g. on FAS test, items with identical meaning in French are not FAS, but T, N and P
“No ifs, ands, or buts”
Scalar Equivalence Measured on the same metric
Numerical value on scale has same degree of intensity or magnitude of the construct
E.g. is the distance between 6 (moderately severe) and 7 (severe) the same in both cultures?
Developing cross-cultural measures Sequential approach
Translate an instrument into another language Simultaneous approach
Conceptualize & develop measure in each culture Set of equivalent items that reflect the same
construct in different cultures Core instrument plus culture-specific
additional components
Strategies for ensuring cross-cultural equivalence Direct translation and comparison
Better translation techniques
Multi-trait, multimethod
Item response theory methods Differential item functioning
Strategies: continued Response pattern method
Factor analysis
Multidimensional scaling
Combined etic-emic approach
Multi-strategy approach
Methods for assessing equivalence Factor analysis
Empirical analysis of how items relate to one another Shows how many concepts scale measures and which
items measure that scale Confirmatory: must have theory about how items go
together Simultaneous factor analysis in different populations Factor structure should be the same Test whether data are similar to be called equal
Same factor pattern-loadings Same goodness of fit
Differential item functioning Related to IRT theory Needed because tests can have matching
factor structures and still be biased DIF analyses
Compare reference and focal groups In translation from English to French, English
reference and French focal
Differential Item Functioning DIF = a different in item score between
two groups who are equal in ability. First step: match on ability (total score)
Internal test of item bias 2nd step: for each score group, compares
performance of reference and focal group on each item
Two types of DIF Uniform
Difference in difficulty between reference and focal group Item may be more difficult for one group
Non-uniform Difference in discrimination between
reference and focal group
When you find DIF or non-factorial equivalence Study reasons why
Content experts
Review item wording, translation, cultural meaning.
Translation Simply translate instrument and administer
it Simple tests of difference: assumes scalar
equivalence Translation-back translation
Issues to Consider Goal: to adapt measure for a new country, or to
make comparisons across countries? Translation or adaptation? Back-translation gives
identity rather than equivalence In most countries the ‘official’ language differs
from the vernacular. Which do we use? We still know little about effect of linguistic
variations within countries
Issues - continued Why was this instrument chosen? Are
these features relevant in another culture? At least some of the content of most scales
will be culture-specific (e.g., some of NHP seen as blasphemous in Arabic countries)
Was the scale developed on a particular cultural group?
Quality of Life Quality of life is subjective & value-
specific Invented in the USA; ¿not universal? Definition will at least vary across cultures
(naïve enthusiasm for QoL) Handicap reflects impairment +
environment, so measures may perform differently in different environments
Translation, or Domination? “…with refinements and changes
introduced here and there in order to convey the meaning of the English questions as accurately as possible…” (A. Leighton)
Words & Concepts An etic approach (phonetic) describes the
physical properties of the word, without referring to its functional meaning: language
The emic approach takes account of the context, meaning and purpose of the word: concepts
Translation Example “Does poor health prevent you from seeing
your friends?”
Meaning of “friend” differs in UK, US, and Australian English
Even more differences between Ami(e), Amigo and Freund
Suggestions Plan cross-cultural applications from the outset Consider relevance of quality of life carefully: omit? Avoid questionnaires! Use ‘DIF’ analyses Run within-country analyses Develop measures within each country Seek core set of universal items (WHO QoL) Make sure the values are explicit