Education for all in action: Measuring teachers’ competences for inclusive education

of the total variance. Factor loadings ranged from .70 to .80, and communalities ranged from .48 to .63. The scale had high internal reliability (α = .94). Self-efficacy in creating high-quality student-interactions. Based on the data distribu- tions and anti-image correlation matrix, four items were deleted (see Table 1). PCA on the remaining 8 items revealed satisfactory KMO-value, anti-image correlations and Bartletts’ test. The scree plot and Kaiser criterion indicated one factor to extract with an eigenvalue 5.18, which explained 64.7% of the total variance. Factor loadings ranged from .70 to .85, and com- munalities ranged from .49 to .72. The scale had high internal reliability (α = .92). Step 2: CFA with in-service teachers. In the second step, the solution that resulted from the first step was checked for in-service teachers using CFA. With regards to self-efficacy, we included four different factors: noticing diversity with six items, enabling high-quality stu- dent-interactions with eight items, creating stimulating learning environments with 13 items, and collaborating with colleagues and parents with 16 items. With regard to beliefs about diverse students, we included four factors geared toward specific groups, being ethnic minority students, disabled students, students from low SES, and essentialist notions regarding the gen- der binary and sexuality with respectively six, six, five, and nine items. For beliefs on the responsibility of the educational field to create education for all, we included three factors

focusing on general school policy, and initiatives geared specifically towards either ethnic minority students or students with a disability, with respectively eight, four and four items. The result of this points to acceptable but not good fit indices (AIC = 155650, X2 = 8030, DF = 3430, p < 0.001, X2/DF = 2.34, RMSEA = 0.048, CFI = 0.760, SRMR = 0.066). Changes were made in order to achieve a better fit. As factor loadings for the items related to collaborat- ing with colleagues were consistently lower (i.e., between .424 and .511), we tested a model with a separate factor pertaining to collaborating with diverse parents (consisting of 10 items) and one pertaining to collaborating with colleagues (consisting of six items). These adaptations led to a better fit (AIC = 154671, X2 = 7125, DF = 3419, p < 0.001, X2/DF = 2.08, RMSEA = 0.043, CFI = 0.807, SRMR = 0.059). In a next step, 13 items were deleted as sug- gested by the modification indices, R-square values or factor loadings (see Table 1). This led to a further improved model (AIC = 133214, X2 = 4765, DF = 2418, p < 0.001, X2/DF = 1.97, RMSEA = 0.041, CFI = 0.846, SRMR = 0.054). In accordance with suggestions by Hu and Ben- tler (1999) and as shown by Coubergs and colleagues (2017), we accept a combination of CFI- values approaching .90 with RMSEA values smaller than .06 and SRMR-values under .08 as good model fit. Factor loadings can be seen in Tables 2 and 3 (note that the loadings for self- efficacy and beliefs are shown in separate tables for lay-out reasons only, as these are tested as

one model within CFA). This table shows loadings above |.50| for all items, with the exception of C2_14, C2_27, C2_29, C5_14, and C5_15. As these items still loaded above |.40|, while delet- ing them was not conducive to the Cronbach’s alpha of the respective factor, this was deemed acceptable. All in all, this results in a model with five factors related to self-efficacy and seven factors related to beliefs, with alpha scores being good for each factor and showing that no items could be deleted in order to get a higher alpha. More specifically, the factors related to self-efficacy comprises “noticing student diversity” consisting of 6 items with α = .87, “enabling high-quality student-interactions” consisting of 6 items with α = .85, “creating stim- ulating learning environments” consisting of 13 items with α = .90, “collaborating with col- leagues” consisting of 3 items with α = .83, and “collaborating with parents from diverse backgrounds” consisting of 8 items with α = .88. The factors relating to beliefs comprises pro- fessional beliefs on different types of diversity, specifically on ethnic minorities (# of items = 6, α = .79), students with a disability (# = 4, α = .78), students from low-SES families (# = 5, α = .76), and essentialist notions on sexuality and the gender binary (# = 8, α = .79), as well as beliefs on the responsibility of the educational field to create education for all, including a PLOS ONE Measuring teachers’ competences for inclusive education PLOS ONE | https://doi.org/10.1371/journal.pone.0291033 November 8, 2023 12 / 22

Table 2. Standardised CFA matrix for self-efficacy on handling diversity. To what extent are you able to. . .? Notice diversity High-quality student- interactions Stimulating learning environment collaborate with parents collaborate with colleagues C1.02 Make time for in-depth individual conversations with all of your students in order to provide more effective support. 0.763 C1.03 Gain insight into the learning needs of an individual student by consciously looking at how he/she responds to different tasks and works in different groupings. 0.686 C1.05 Gain insight into a student’s plans and dreams for the future. 0.674 C1.06 Start a conversation with a student who is not attentive or is having a difficult time outside of the classroom. 0.688 C1.07 Gain insight into social relationships among students. 0.775 C1.09 Gain insight into the students’ feelings about their family situation. 0.817 C3.03 Allow students with learning difficulties to be helped by other pupils. 0.657 C3.05 Give tasks where the students have to work together to complete the task successfully (for example, each having a different role). 0.619 C3.06 Provide feedback on how students work together. 0.765 C3.07 Create space in or outside the classroom to support students in the resolution of conflicts. 0.761 C3.10 In group work, ensure that all pupils get to work with others from all across the class? 0.678 C3.12 In the case of bullying, discuss a plan of action with the students involved. 0.710 C4.01 Ensure that teaching materials reflect diversity in society. 0.580

C4.04 Use a wide range of evaluation methods in order to evaluate students in a broad a way as possible. 0.697 C4.06 Specifically check that students with a language delay have understood a question. 0.693 C4.07 Enter into dialogue with students about their results. 0.547 C4.08 Occasionally use a short moment of evaluation (e.g., quiz) to tailor your lesson in a more nuanced way to the students’ needs. 0.693 C4.10 Give students opportunities beyond traditional tests and exams to demonstrate their knowledge and skills (e.g. through portfolios, writing tasks, oral presentations). 0.613 C4.11 Allow students to give input about content that they would like to cover in lessons. 0.685 C4.12 Have students evaluate your lessons. 0.537 C4.13 When managing the pace of your lessons, take account of students who work faster/slower than the others. 0.731 C4.14 Offer a variety of activities so that students can choose what to do themselves. 0.644 C4.16 Allow students to choose whether or not to use certain tools/ support. 0.719 C4.18 Use a variety of teaching materials and media which invite pupils to draw on different senses. 0.686 C4.19 When necessary, adapt your learning objectives (knowledge and skills) to take account of differences between students (e.g., by creating main and advanced learning goals). 0.678 C5.01 Make parents from different backgrounds feel comfortable about coming into school. 0.819 C5.02 Help parents to support their children to do well in school. 0.870 (Continued) PLOS ONE Measuring teachers’ competences for inclusive education

PLOS ONE | https://doi.org/10.1371/journal.pone.0291033 November 8, 2023 13 / 22

factor on general school policy (# = 5, α = .74), and factors with initiatives geared specifically towards ethnic minority students (# = 4, α = .70), and students with a disability (# = 4, α = .73). Scale-scores. With regard to beliefs, analysis of variance showed that there were signifi- cant differences on in-service teachers’ belief scores depending on the dimension (V = .825, F(6, 514) = 101.26, p < .001). More specifically, teachers’ scores varied on average between 3 and 5 on scales ranging from 0 to 6 (see Table 4), indicating that teachers’ beliefs varied from a neutral position to “agree” depending on the specific scale. The post-hoc Bonferroni test revealed that, with the exception of teachers’ beliefs on SES students and their beliefs on school policy specifically geared towards disability students (p < .887), all scale scores dif- fered significantly from each other. Hence, teachers scored highest on their belief on schools’ responsibility to have a general policy on diversity, followed by holding most favourable beliefs with regards to students’ gender and sexuality, and students with a dis- ability, followed by ethnic minority students. Teachers held the least positive beliefs on the responsibility of a school to have a policy specifically geared towards ethnic minority stu- dents, and scored somewhat higher on their beliefs on SES students and the responsibility of a school to have a policy specifically geared towards disability, which did not differ signif- icantly (as reported above).

As shown in Table 4, in-service teachers tended to score on average between 5 and 6 on the efficacy-scales ranging from 0 to 8, indicating that teachers feel more or less “reasonably” effi- cacious. Analysis of variance showed that there were significant differences on efficacy scores depending on the dimension (V = .438, F(4, 520) = 101.26, p < .001). The post-hoc Bonferroni test revealed that teachers did not differ significantly in their efficacy in enabling high-quality interactions between students and collaborating with colleagues. These were the dimensions on which teachers tended to feel most efficacious when compared to the other dimensions (p < .001), with creating stimulating learning environments taking a middle position (p < .01), while noticing student diversity and collaborating with parents did not differ significantly from each other and were the dimensions that teachers rated themselves least efficacious on (p < .01). Table 2. (Continued) To what extent are you able to. . .? Notice diversity High-quality student- interactions Stimulating learning environment collaborate with parents collaborate with colleagues C5.03 Involve the parents of students with special needs in their children’s educational career. 0.885 C5.04 Adapt the way you communicate with different kinds of families (e.g. single parents, LGBT+ parents, non-native speakers. . .). 0.760 C5.06 Use the insights that parents give you about their child. 0.706 C5.07 Establish a good relationship with all parents, even if you do not like them. 0.720

C5.14 Always be available for questions from parents during school hours. 0.480 C5.15 Allow parents to give some input about my lessons. 0.451 C5.11 Integrate lesson ideas from colleagues into your own teaching practice. 0.769 C5.12 Ask colleagues for feedback to improve your teaching. 0.801 C5.13 Create new teaching methods or materials together with colleagues in order to support students with learning difficulties. 0.800 https://doi.org/10.1371/journal.pone.0291033.t002 PLOS ONE Measuring teachers’ competences for inclusive education PLOS ONE | https://doi.org/10.1371/journal.pone.0291033 November 8, 2023 14 / 22

Table 3. Standardised CFA matrix for beliefs in handling diversity. Beliefs on different types of diversity Schools’ responsibility for EfA To what extent do you agree with . . .? Ethnic minorities Gender Disability SES Ethnic minorities Disability General policy C2.01 Ethnic and cultural diversity is a valuable resource in education. 0.622 C2.03 If there are more “native-born” pupils in a school, it means that academic achievement will be higher across the board. 0.451 C2.04 If an additional language is spoken at home, the student will fall behind in their learning. 0.608 C2.06 Immigrant students are not as good at mathematics as native students. 0.635 C2.07 Students who speak a different language at home will never speak Dutch properly. 0.647 C2.08 The more immigrant students in a school, the more discipline problems the school will face. 0.725 C2.11 Many students experiment with their sexuality just to get noticed. 0.557 C2.14 LGB teachers (lesbian, gay, bisexual, transgender), have the right to be open with parents about their sexual orientation. 0.421 C2.15 In order for their time in school to go smoothly, it is better for LGB students not to openly display their sexual orientation. 0.709 C2.16 I feel sorry for students who grow up in an LGB family because it is not easy for them. 0.657 C2.25 Boys shouldn’t wear earrings or nail varnish when in school. 0.573 C2.27 Two boys should be able to dance together for the entire evening at the school dance without attracting undue attention. 0.477 C2.28 I find it difficult to understand transgender students. 0.675

C2.29 I think it’s good that girls are not asked to help out with jobs in school that involve heavy lifting. 0.479 C2.20 Students with a disability always score worse on tests than other students. 0.618 C2.21 Students with a disability reduce the learning opportunities for the other students in the class. 0.681 C2.22 Students with a disability often abuse the support that they receive. 0.756 C2.24 I think that many teachers show too much understanding for the behaviour of students with a disability. 0.677 C2.33 Underprivileged parents are often less interested in their children’s progress in school than other parents. 0.669 C2.34 It is difficult to be sympathetic towards poorer students if they or their parents always have the latest mobile phones or gadgets. 0.618 C2.35 Schools that educate many underprivileged students have lower standards. 0.697 C2.36 Underprivileged students rarely succeed in difficult subjects because they do not have supportive parents. 0.590 C2.37 It is acceptable for teachers to have higher expectations of students from well-off backgrounds. 0.545 C6.01 The school should provide specific services for students who want to follow religious practices (e.g., prayer room, halal/kosher food). 0.508 C6.02 The school must allow students with a migration background to speak a language other than Dutch at school. 0.738 C6.04 The school library should have books in the different home languages of the students. 0.676 C6.05 It is important to encourage students of immigrant origin to be proud of their ethnic and cultural background. 0.513

C6.07 It is time that we give children with a disability a full place in mainstream education. It is their right. 0.765 (Continued) PLOS ONE Measuring teachers’ competences for inclusive education PLOS ONE | https://doi.org/10.1371/journal.pone.0291033 November 8, 2023 15 / 22

Discussion While the pursuit of inclusive education is influencing policy agendas of countries across the globe [3], it can be considered a wicked problem as it is characterised by normative plurality, institutional complexity and scientific insecurity [8,10]. This article aims to help grasp the issue by validating the DISCO-instrument, which measures teachers’ beliefs and sense of effi- cacy towards diversity in education. In what follows, we discuss not only the factorial structure arising from the data, but also explore what this unveils on teachers’ thinking about diversity in the classroom. The questionnaire consists of two parts: beliefs and sense of efficacy. Teacher beliefs consist of 36 items in total, and includes beliefs about student diversity and beliefs about the Table 3. (Continued) Beliefs on different types of diversity Schools’ responsibility for EfA To what extent do you agree with . . .? Ethnic minorities Gender Disability SES Ethnic minorities Disability General policy C6.08 It is sensible to not send students to special educational support too quickly. 0.671 C6.09 The school’s infrastructure must be made accessible at all levels to people with physical and sensory disabilities (vision, hearing, motor). 0.548 C6.10 You cannot expect the teacher to meet the needs of a child with a disability in mainstream education. 0.580 C6.13 Teachers must be capable of working with students from different home situations. 0.608 C6.14 Students from families with financial problems should be provided with

appropriate support (e.g. payment plan, special support fund for students who cannot pay the school fees). 0.688 C6.16 A teacher can make a difference for students from all kinds of home environment. 0.527 C6.21 As a school, it is important to break the traditional divide between subjects that are stereotypically for boys or for girls. 0.571 C6.44 It is every teacher’s job to contribute to a school policy that is mindful of diversity. 0.629 https://doi.org/10.1371/journal.pone.0291033.t003 Table 4. Descriptive statistics of scale-scores. Mean SD Range N Efficacy in Noticing diversity 5,06 1,48 0–8 524 Enabling interactions 5,88 1,23 0–8 524 Creating learning environments 5,32 1,34 0–8 524 Collaborating with parents 5,09 1,55 0,13–8 524 Collaborating with colleagues 5,89 1,56 0–8 524 Beliefs on Ethnic minority students 3,78 0,98 0,5–6 520 Students with a disability 4,20 1,00 1–6 520 The gender binary & sexuality 4,83 0,85 1,75–6 520 SES students 3,38 1,10 0,6–6 520 General school policy 5,00 0,70 2,40–6 520 Policy geared towards ethnicity 2,93 1,21 0–6 520 Policy geared towards disability 3,49 1,12 0–6 520 https://doi.org/10.1371/journal.pone.0291033.t004 PLOS ONE Measuring teachers’ competences for inclusive education PLOS ONE | https://doi.org/10.1371/journal.pone.0291033 November 8, 2023 16 / 22

responsibility of education to create education for all. The beliefs on student diversity consist of several dimensions, specifically teachers’ professional beliefs about students with an ethnic minority background, with a disability, from lower socio-economic backgrounds, and essen- tialist notions on the gender binary and sexuality. While these dimensions match with typically delineated categories of at-risk students, this was not entirely the case for gender and sexual orientation. Interestingly, even though items on both LGBT students and gender norms were included, analyses show that both pre- and in-service teachers tend to think of these as one overarching construct. This is in line with the theoretical concept of heteronormativity, which highlights the way in which normative ideas on gender expression and sexuality are interwo- ven [58]. Hence, the validation of the DISCO-instrument lends further support to the con- struct of heteronormativity, not just from a theoretical perspective but within the minds of teachers as well. The responsibility-items tap the extent to which teachers believe it is the responsibility of the educational field to create maximal developmental opportunities for diverse students. This includes several dimensions, including one about general school policy, which encompasses both general items (e.g., “It is every teacher’s job to contribute to a school policy that is mindful of diversity”) as well as items referring to SES- and gender-issues (e.g., “Students from families

with financial problems should be provided with appropriate support (e.g. payment plan, spe- cial support fund)”, “As a school, it is important to break the traditional divide between sub- jects that are stereotypically for boys or for girls.”). Other dimensions encompass items on school policy directed towards specific diversity-groups, with one dimension specifically geared towards students with a migration background, and another geared towards students with a disability. This factorial structure suggests some interesting things about the way teach- ers think about school policy and the educational field’s responsibility on EfA. For instance, issues regarding SES and gender are apparently being regarded as “commonplace enough” to be integrated within general school policy. Conversely, the needs of ethnic minority students and those with a disability are seen as being “too different” and warrant their own specific poli- cies and guidelines. Previous research has shown that Flemish teachers tend to have a lot of questions on how to handle students’ multilingualism and religiosity [47]. Furthermore, Flan- ders historically has a high rate of students segregated into special education when compared to other European nations [59], and has only recently made substantial steps in integrating stu- dents with a disability in mainstream education [47]. Hence, it stands to reason that this is con- tributing to teachers seeing policies for both ethnic minority students and those with a disability as being “special”. It would be interesting for future research to explore to what

they experience when providing education to students from low-SES family backgrounds [11]. Qualitative research would be well-placed to thoroughly investigate and make sense of this ambiguous stance of teachers. The second part of the questionnaire contains 36 items considering teachers’ sense of effi- cacy, and is organized in five dimensions. The first dimension taps teachers’ efficacy in notic- ing student diversity (f.i., students’ background, interests, well-being, . . .), the second the extent to which teachers feel capable to design a classroom which capitalizes on the strengths and needs of their students, and the third measuring the extent to which teachers feel capable to create high-quality interactions among students. The fourth and fifth dimension tap teach- ers’ perceptions of the degree to which they feel capable to collaborate with colleagues and diverse parents respectively. The analyses on the scale-scores show that teachers tend to feel most efficacious in both col- laborating with colleagues and in creating high-quality interactions among students. This is followed by creating stimulating learning environments for diverse students. Note that this dimension includes a lot of items related to providing differentiated instruction, with using a variety of instructional and evaluation methods, and stimulating the interest and engagement of students. As such, this dimension connects to the core of teachers didactical competencies [61,62]. Consequently, the ranking of these dimensions may come as no surprise, with teachers

feeling reasonably efficacious in this dimension, while at the same time continuing to see opportunities for further growth and improvement. At the same time, noticing student diver- sity and collaborating with diverse parents are the lowest rated efficacy-dimensions. Neverthe- less, in order to capture students’ attention and engagement, theories on differentiated instruction emphasize the importance of taking into account the social environment of stu- dents and their individual interests [62]. We could speculate that the relatively low score on noticing diversity reflects the idea among teachers that this is not a must, but merely a nice extra, second to more concrete didactical approaches. Qualitative research with teachers would be well-placed to explore the reasons for teachers’ efficacy-assessment on this dimen- sion. Furthermore, the low score on collaborating with diverse parents is in line with previous research in Flanders, indicating that parents’ involvement is often only expected or even toler- ated under specific circumstances, such as coming to the parent-teacher contact moment or helping out with the school fair [63]. Nevertheless, research has shown that creating strong connections between the school and the home environment is conducive to students’ school belonging and achievement [64,65], and could be an important lever in creating quality educa- tion for all [11]. Note that the scales on efficacy in collaboration with parents and colleagues originally started out as responsibility belief-scales, which had to be reworked due to ceiling-effects.

Interestingly, the data shows that teachers combine the highest efficacy-ratings in collaborating with colleagues with the lowest efficacy-scores in collaborating with parents. This shows both the nuances and complexities in (student-)teachers’ assessments of what they can and should do. That is, our validation process suggests that (student-)teachers are able to recognize that collaboration is something they should do, while simultaneously admitting to low abilities in collaborating with one partner and high scores in collaborating with another. In conclusion, this article discusses the DISCO-instrument, which measures teachers’ beliefs and efficacy for creating quality education for diverse students. In the context of EfA being considered a wicked problem, we suggest that DISCO cannot only help researchers to grasp the state of affairs of a specific school or educational system, but can support policy mak- ers and principals in making evidence-based decisions on the professionalisation needs of their school teams. PLOS ONE Measuring teachers’ competences for inclusive education PLOS ONE | https://doi.org/10.1371/journal.pone.0291033 November 8, 2023 18 / 22

Limitations While this instrument is able to grasp teachers’ beliefs for inclusive education as well as a self- assessment of their skills, it remains to be seen how the DISCO-instrument connects to other aspects of competency such as knowledge and actual classroom behaviour. Furthermore, the validation-process in this study remains largely focused on structural validity, while it has been argued that a full validation-process should encompass a.o. the stability of the instrument, as well as concurrent, discriminant and criterion-related validity [66]. Especially a cross-national comparison could give us some interesting insights into how contexts, with their specific edu- cational realities and policies, shape teachers’ thinking and competences on inclusive educa- tion. Similarly, it would be interesting to explore to what extent respondents report different beliefs and self-efficacy scores depending on their own intersectional positions. We were unable to explore this as our data did not include demographic information beyond respon- dents’ age, gender and educational background. However, it stands to reason that our sample included few voices from minoritized groups as the Flemish teaching population tends to con- sist overwhelmingly of white, middle class, cisgender, straight, able-bodied women, with for instance only 3.2% of the teaching population being of ethnic minority descent [67]. Lastly, we suggest that mixed method or qualitative methods might be interesting to further understand the processes underlying teachers’ answers to the DISCO-survey and hence their

beliefs and self-efficacy assessments regarding inclusive education. For instance, future research, could use think-aloud procedures to gain a deeper insight into how teachers think about specific features of inclusive classrooms, including how they assess the importance of noticing diversity or their ambiguous stance regarding professionals beliefs versus policy aimed at low-SES students. Author Contributions Conceptualization: Wendelien Vantieghem, Iris Roose, Karin Goosen, Piet Van Avermaet. Data curation: Wouter Schelfhout. Formal analysis: Wendelien Vantieghem. Investigation: Wendelien Vantieghem, Iris Roose, Piet Van Avermaet. Methodology: Wendelien Vantieghem, Karin Goosen. Supervision: Piet Van Avermaet. Writing – original draft: Wendelien Vantieghem. Writing – review & editing: Wendelien Vantieghem, Iris Roose, Wouter Schelfhout. References 1. Banks J, Cochran-Smith M, Moll L, Richert A, Zeichner K, LePage P, et al. Teaching diverse learners. In: Darling-Hammond L, Bransford J, editors. Preparing teachers for a changing world: What teachers should learn and be able to do. San Francisco, CA: John Wiley & Sons; 2007. p. 232–74. 2. Forghani-Arani N, Cerna L, Bannon M. The lives of teachers in diverse classrooms. OECD Education Working Papers. 2019; 198. https://doi.org/10.1787/8c26fee5-en. 3. Burns T, Shadoina-Gersing V. Educating teachers for diversity: meeting the challenge: Paris: OECD; 2010. 4. Van Mieghem A, Verschueren K, Petry K, Struyf E. An analysis of research on inclusive education: a

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