Funciones Pragmáticas

Insights gained from the focus group interview provided conceptual

definitions of the concept of SE in TAs supporting children with ASD. This information, combined with the evidence gained from the literature review, enabled items to be written to explicitly capture the specific construct being explored.

5.3.2.2.1. Sampling

An opt-in participant population completed the TASCA, with limitations reflecting those identified above. Head teachers who felt that their staff were efficacious might have forwarded the survey link, whereas those who had doubts about their staff’s efficacy might not have done so. Likewise, it is not possible to ascertain why some staff accessing the questionnaire decided not to provide consent, or to know how these staff differed from those who did complete the survey.

All participants were aware of the anonymity and confidentiality of their responses in order to mediate against socially acceptable responses.

Additionally the time at which surveys were taken suggested that many were completed out of the school context. This physical and psychological

distance from the school might have impacted upon the responses given.

5.3.2.2.2. Response categories

Participants completing the TASCA appeared to use response choices across the 0-100 continuum offered, varying by item. Thus, responding in

gaps or jumps of 5-10 as noted by DeVellis (2012) to be a possible difficulty with such response scales was not evidenced.

5.3.2.2.3. Survey length

The researcher was aware of the practical implications of questionnaire length and response burden, with lengthy questionnaires and low response rates having an impact on the validity of responses in a number of ways: volunteer bias (Roth & Bevier, 1998); increased use of the modal response category (Kraut, Wolfson, & Rothenberg, 1975); and identical responses for all items (Herzog & Bachman, 1981).

It was deemed important to present sufficient items to capture all elements of the construct, to incorporate the additional research evidence and the pilot feedback, resulting in a 36 item survey with 7 demographic data items. It proved challenging to devise a questionnaire with fewer items. However, the pilot questionnaire took 7-15 minutes, thus indicating that it might be

manageable within recommended time scales (Galesic & Bosnjak, 2009; Handwerk, Carson, & Blackwell, 2000). In practice, participants spent

between 5 and 95 minutes completing the scale. It is not known whether any breaks were taken during completion of the scale, or how long these were. Subsequent item analysis indicated that the survey could be shortened without reducing reliability.

5.3.2.2.4. Data Analysis

Descriptive statistics were used to analyse scaled items within the TASCA scale using SPSS® 23.0.

Despite there appearing to be rigour within the quantitative elements of the analysis, this analysis clearly relied upon the questions that had been formulated, as identified above. An instrument can yield consistent, reliable

results, but will be invalid if it is measuring the “wrong” construct. It is felt that clear steps were taken to ensure that the construct was clearly identified.

Demographic data was gathered. It would have been more helpful to ask how long a TA had worked with pupils with ASD rather than as a TA, since this figure cannot be used as an indicator of mastery.

Factor analysis could not be completed because of the number of

questionnaire items and the number of surveys completed (see 5.2.2.2.7.). However, this might have provided useful information about the

questionnaire and had implications for its further use.

5.3.2.2.5. Use of an online survey

The online survey approach proved to be an effective way in which to gain a relatively high number of responses within a short time period. Over 4 weeks, 83 surveys were initiated and 50 completed. The approach is highly cost- effective and the software intuitive.

5.3.2.2.6. Validity

In devising the TASCA, it was important to ensure validity in relation to the target population, therefore, focus group data, in conjunction with relevant research, were combined to create a tool with content validity (DeVellis, 2012). Piloting with an expert panel was carried out as a further check to ensure that items were representative of the construct that the questionnaire was designed to measure. This enabled the removal of any items that were not representative of the construct, thus supporting claims of content validity. Semantic, editorial and time issues were additionally identified and

amendments made. All pilot respondents agreed that the survey clearly reflected the activities which would tap into SE for TAs supporting children with ASD, therefore the researcher had increased confidence in its validity.

In order to ascertain validity of the TASCA, it would be necessary to accumulate evidence across time, settings and samples to build a scientifically sound validity argument. Thus, establishing validity is an

ongoing process of gathering evidence (Kane, 2006). Additionally, it is noted that reliability and validity are not properties of the survey instrument, per se, but of the way in which surveys are scored and interpreted (Cook &

Beckman 2006).

In order to standardise the TASCA, factor analysis would be required. The opposing perspectives existing in relation to recommended sample size were considered. One indicates that N, or sample size, is key, with Gorsuch (1983, cited in DeVellis, 2012), and Kline (1979, cited in DeVellis, 2012)

recommending at least 100 participants, and Cattell (cited in Zoski & Jurs, 1996) recommending at least 250. Others contend that it is the subject to variable ratio, or p, that is important, with Hatcher, Barends, Hansell and Gutfreund (1995) recommending that the number of subjects should be 5 times the number of variables, or 100, whichever is the larger, and Garson (2008, cited in DeVellis, 2012), suggesting 10 subjects per item. Based upon these assertions, the TASCA would need to have been completed by many more participants. For this reason factor analysis was deemed inappropriate.

5.3.2.2.7. Reliability

The preliminary reliability analysis suggested that the TASCA was a highly reliable instrument. However, Schmitt (1996) cautions that Cronbach’s alpha is not a good measure of a scale’s uni-dimensionality (measuring a single concept) as is often assumed. Thus, when developing a scale from scratch, the researcher should first run a factor analysis, to assess the uni-

dimensionality of the scale before carrying out a reliability analysis, to assess the internal consistency of the item scores on the scale (Schmitt 1996). Sijtsma (2009) argues that Cronbach’s alpha can be overestimated as an indicator of reliability, however, DeVellis (2012) argues for its utility, being

indicators of reliability. It was therefore felt to be appropriate within this exploratory study.

5.3.2.2.8. Next steps

After item analysis and further piloting and dissemination of the reduced survey, a domain specific standardised scale to examine TA SE in relation to ASD (Brouwers & Tomic, 2001; Higgins, 2009) could be produced.

5.3.2.3. Phase 3: What SE beliefs do TAs report in relation to supporting