the sample population, sample frame and sample methods (Dillman et al., 2009). The first step in selecting a sample is to define the survey population. Survey population refers to all of the elements such as individuals or organisations that a researcher wants to generalise survey findings (Dillman, et al., 2009). The study population was ECTs within the Sydney metropolitan area. This area was chosen to assist making the recruitment manageable. That is, a concerted effort was made to recruit ECTs through direct contact with schools, and focusing on areas within the Sydney metropolitan areas where ECTs tend to be located (e.g., Sydney south-west, west). This focus would not have been readily available if recruiting teachers from outside the metropolitan Sydney area.
Choosing ECTs from the Sydney metropolitan area provided opportunities to engage ECTs working in a diverse range of demographic areas. It was proposed that schools in this area would pose the range of issues that had been identified in the previous literature as possible stressors for ECTs (e.g., challenging behaviour, social disadvantage) due to the diverse student population (Burridge, Buchanan, & Chodkiewicz, 2009).
There are over 5,000 education graduates each year in NSW (NSW Teachers Federation, 2013), in both secondary and primary education. Although NSW Teachers Federation (2013) reported the estimated number of graduates from initial teacher education programs, there was no published data available with regard to the number of graduates from initial teacher education programs – primary education. Also, no published data was available on the number of ECTs employed at primary schools in the Sydney
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ter v ie w ax ial and supp ort ing op en co desmetropolitan area. If the number of primary education graduates was assumed to be 2,500 per year, the approximate number of the survey population was 500 per year in the Sydney metropolitan area. The participants in the current study were ECTs who had teaching experience of five years or less. Thus, the approximate population of the current study was 2,500.
After the survey population was established, the sample frame needed to be considered. The sample frame is a list of the survey population (Groves, Fowler, Couper, Lepkowski, Singer, & Tourangeau, 2009). The sample frame of the study was the list of teachers who were in the first five years of teaching at primary schools in the Sydney metropolitan area. The researcher was unable to obtain a list of primary ECTs working at primary schools in the Sydney metropolitan area for the current study. This was because the name, contact details, and email addresses of the primary ECTs working at primary schools in the Sydney metropolitan area is confidential and not available to the public. The researcher was able to obtain only a list of primary schools in the Sydney metropolitan area through public domain sources and general contact details for each school. The researcher planned to contact ECTs through their principal.
Next, the sample was drawn based on a sample frame. The sample represents the survey population, and consists of those invited to partake in the survey. The sample size can be the same as the survey population or smaller than the survey population. If the size of the sample is smaller than the survey
population, the completed sample size needs to be determined as it affects the precision of the survey results (Dillman et al., 2009). The sample size can be flexible depending on the method of analysis, subgroups of the survey population or available funding than strictly rely on the sample size equation (Dillman et al., 2009).
𝑁𝑠 = (𝑁𝑝)(𝑝)(1 − 𝑝)
(𝑁𝑝− 1)(𝐵 𝐶⁄ )2+ (𝑝)(1 − 𝑝)1
The approximate sample for the current study was 334 with a ±5% margin of error, with a confidence level set at 95% and a 50/50 split. The sample size was an approximated size as there was no way to obtain precisely the number of survey population.
Nonresponse rates should be considered when the sample is drawn. Generally, 20-30% of a sample complete and return the survey immediately (Nardi, 2006). Thus, to minimise nonresponse rates, all
principals in primary schools in the Sydney metropolitan area were contacted and asked for their permission to distribute the survey to ECTs in their schools. However, getting contact with ECTs proved to be difficult
1 𝑁
𝑠= the 𝑐𝑜𝑚𝑝𝑙𝑒𝑡𝑒𝑑 sample size needed for the desired level of precision.
𝑁𝑝= the size of the population
p = the proportion of the survey population expected to choose one of the two response categories
B = margin of error (i.e., half of the desired confidence interval width): .03 = ±3% C = Zscore associated with the confidence level (1.96 corresponds to the 95% level)
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ter v ie w ax ial and supp ort ing op en co desthe school, participation in other research projects, and a declaration that no ECTs worked at their school. A total of 87 ECTs participated in the survey. Eighty-two (82) participants completed the on-line survey and five participants completed a paper survey. Eight surveys were withdrawn from the data analysis because the survey had not been completed. Therefore, 79 completed surveys were used for analysis. The implications of this low return rate will be discussed in the Discussion chapter Six.