ACQ Vol 13 no 2 2011

normal distribution and the use of scores such as standard scores/percentile ranks allow us to determine where a child’s score fits in the normal distribution. While they should be used with caution, they do allow us to interpret a score. A chart of the normal distribution is a good visual reference to explain standardised scores to parents/carers (see left). In contrast, other scores such as age equivalents can be dangerous. They do not tell us the degree of impairment/ difference. They do not say a child is performing the same as another child at that age equivalent (if a child aged 12 years obtains an age equivalent score of 5 years, it does not mean he or she is performing the same as a 5-year-old) as the score is usually calculated on a total raw score and the pattern of responses can be completely different. Age equivalent scores do not measure change and should not be used to state, for example: “he made 6 months progress in 3 months”. 5 Criteria to evaluate a test against, which allow us to make an informed decision when we purchase a test When we plan to buy a standardised test, we need to ensure it has strong psychometric properties. The books outlined above (see no. 2) cover these concepts in detail. In brief, we want a standardised test to provide information about the standardisation sample (so we know if it is valid to compare our client to the norms), as well as reliability and validity data – so we know that the scores will be consistent and reflect the areas the test aims to test, and that the test administration and scoring are clear. It is tempting to skip through the manual when considering purchase but this is the most important part of evaluating a test! 6 A well-developed standardised test I have found the Clinical Evaluation of Language Fundamentals (4th ed.) (CELF-4) and the Clinical Evaluation of Language Fundamentals, Preschool (CELF-P) to be good value for money and they have strong psychometric properties (as well as the benefit of local “norms”). These tests are available from Pearson at http://www. pearsonpsychcorp.com.au/productdetails/85/1/42 and http://www.pearsonpsychcorp.com.au/productdetails/84 7 Access to evidence in the research literature Evidence based practice is as important to assessment as it is for intervention. When we come to develop and use non-standardised approaches to collect assessment data, we must still make sure they are reliable and valid as well as driven by theory. Speech Pathology Australia has provided a position statement that makes a great starting point: http:// www.speechpathologyaustralia.org.au/library/position_ statements/EBP_Position_Statement.pdf And my favourite resources include: • Dollaghan, C. (2007). The handbook for evidence based practice in communication disorders . Baltimore: Paul H. Brookes • SpeechBite website: http://www.speechbite.com/ • http://www.ciap.health.nsw.gov.au/specialties/ebp_sp_ path/ 8 A broad range of assessments in the “tool kit” There are many times when it is not appropriate to use standardised tests – whether broad spectrum or specific.

These include assessment of children from a range of cultural and linguistic backgrounds and children with severe disabilities. In fact, for assessment to be balanced, it should always include information collected in different ways. We need to use standardised but not norm-referenced tests, criterion referenced assessments, non-standardised protocols, dynamic assessment, observation, and language sampling. We need to collect our data from a wide range of people involved in the process, including significant others, through interviews, observation, and questionnaires. 9 Discourse based sampling methods and analyses

Dr Suze Leitão is a clinician, researcher, and lecturer in speech pathology at Curtin University in Western Australia. She has been teaching a unit about assessment for a few years and it has given her much to think about in her own clinical practice! Her top 10 is a mix of her thoughts and resources that have had an influence on her assessments of paediatric clients. I don’t think I could survive without this rich source of information. I often go to the website for information and the listserv discussions – a new “nugget” pops up regularly and I have found out about many new assessments, assessment protocols, and resources this way! We are seeing increasing use of language sampling in a range of text and discourse genres. One method of sampling that is very practical and has been field-tested with hundreds of children is the Westerveld and Gillon language sampling protocol available for free from http:// www.saltsoftware.com/salt/downloads/NewZealand.cfm The systematic analysis of language transcripts (SALT) is also increasingly used in clinical practice and a lot of useful information on this approach is available on their recently updated website: http://www.saltsoftware.com/ 10 Caroline Bowen’s website

Correspondence to: Dr Suze Leitão email: S.Leitao@curtin.edu.au

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ACQ Volume 13, Number 2 2011

www.speechpathologyaustralia.org.au