Mixed methods research within a multiple case study framework offers the opportunity to gather data from a range of sources. Typically, case study
researchers will use multiple sources of data providing multiple measures of the same phenomenon and use these measures to triangulate the data to confirm the findings and increase the validity of the research (Stake, 2006; Yin, 2014). Methods may include interviews, direct and participant observations, surveys using questionnaires, and document analysis (Yin, 2014). In this study Likert- type scale and open-ended questions within a questionnaire, semi-structured interviews and document analysis were the main sources of data collection. Participant observations were not used in the data collection as PBL occurs over extended periods of time, and data from short observation periods may not add valid understandings of PBL implementation.
a. Surveys using Questionnaires
Questionnaires administered via web tools, such as Survey Monkey, are popular in research as they are easy to conduct, have the potential to reach large groups of people, and gather larger amounts of data (Ary, Cheser Jacobs, Sorensen, & Walker, 2013). Questionnaires usually contain close-ended
questions where relevant responses can be determined and some open-ended questions, when the researcher is not able to pre-determine the range of
possible answers to a question, and the participant is able to respond freely (Ary et al., 2013; Johnson & Christensen, 2014). In this research open-ended questions were used, as well as Likert- type item questions. Likert-type item questions assessed participant attitudes towards PBL by their responds to the statements on a five point continuum from strongly disagree to strongly agree. An advantage in using Likert-type scales is that numbers can be assigned to the response categories giving ordinal data that can be used to calculate some statistical measures such as frequency, median and mode as well as correlations with other variables (Ary et al., 2013). Due to the response categories not being part of a linear continuous scale, it is not appropriate to
calculate the mean and standard deviation as a measure of central tendency (Ary et al., 2013).
The use of a questionnaire adds to the richness of the data collected about the participants’ perceptions of the phenomenon, as it is administered in a cross- sectional manner at a given point in time. It allows the researcher to use the data from the questionnaire to purposefully sample individuals to interview in the next phase of the research (Creswell & Creswell, 2018).
In this study, cluster sampling, where a group of individuals are naturally together (Ary et al., 2013), was used to distribute a separate questionnaire via Survey Monkey to all the teachers in the case study school and to groups of students who were currently involved in PBL at the NCEA level. Both teacher and student questionnaires contained open and closed questions that collected data on demographics and perceptions towards PBL in the NCEA context (see Appendices B and C). The student questionnaire, given to the students who were currently taking part in PBL at the NCEA level in the case study schools, also had a second purpose. This was to gain data on the motivation of the learners who were engaging in PBL. The relevant questions for the motivation scale were from Pintrich’s Motivated Strategies for Learning Questionnaire, commonly refered to as MSLQ (Pintrich, Smith, García, & McKeachie, 1991), and adapted for a PBL context. The questions used relate to the value
component of goal orientation and task value, and the expectancy component of control of learning beliefs and self-efficacy for learning and performance. It is rated using a seven point Likert-type scale on a continuum from 1= not at all true of me to 7= very true of me. The MSLQ also has sections containing questions on test anxiety and learning strategies related to metacognition. These questions were not used as the data gathering was occurring early in the school year and the learning stategies that may be developed as the PBL continues through the year, may not be evident at the time of the data
collection. However, the students’ beliefs about their ability to succeed in a PBL environment and the values and goals they have about their learning, may have an impact on their perceptions about PBL. By gathering data on motivation levels, purposive sampling of students with high levels of motivation and
students with average to low levels of motivation were randomly selected for participation in focus group interviews, once consent was gained.
b. Semi-structured individual and focus group interviews
Interviews enable the researcher to understand, in greater depth, the views of others about their perceptions and experiences of phenomenon, so that the researcher can make meanings about the phenomenon through their analysis of the content of the interview (Josselson, 2013; Punch & Oancea, 2014).
Semi-structured interviews are useful in data collection as there are a sequence of themes that are explored by some prepared structured open-ended
questions, but allows for flexibility to ask follow-up questions to probe and unpack important ideas that emerge from the interviewee answers (Kvale, 2007). Through semi-structured open-ended questioning, the researcher gains an in-depth insight into the interviewees’ perceptions about the phenomenon. Semi-structured interviewing does require careful planning, such as organising the logistics of the interview and scripting open-ended questions, as well as some potential probing and clarifying questions, to maximise the effectiveness of the interview. (Huby et al., 2011; Kvale, 2007; Punch & Oancea, 2014).
Semi-structured focus group interviews, also using open-ended questions, are more complex for the researcher to manage than interviews with individuals. The researcher has a facilitator role, establishing rapport and guiding
conversation by asking questions but allowing for discussions to occur within the group in response to those questions (Punch & Oancea, 2014). People management is important in group interviews so that the group interactions are balanced and participants have equal chance of contributing their thoughts (Punch & Oancea, 2014). Focus group interviews can be advantageous to researchers as the interaction between the participants potentially can reveal greater insights about the participants’ perceptions than is the case with single researcher-participant interviews (Ary et al., 2013; Punch & Oancea, 2014). However, researchers need to be mindful of the potential for group dynamics to influence the views of individuals that are expressed (Ary et al., 2013).
In each case study school, through self-identification in the questionnaire, it was anticipated that teachers with current PBL experience would be interviewed
separately. Focus group interviews were used with students, rather than individual interviews, as they may be more comfortable in a group of peers when interviewed by an unknown researcher.
c. Document analysis
Documents such as unit plans, assessment tasks, and other policy documents are useful to gather as they help to triangulate data collected from other
sources, such as semi-structured interviews (Yin, 2014). This may corroborate the data or may introduce new information that contradicts other sources of data, and therefore, prompting further investigation (Yin, 2014). In this study, documents relating to the study that were examined were PBL process outlines, information provided to whānau and students, project templates, and
assessment rubrics.