Use of Control Charts and Scientific Critical Thinking in Experimental Laboratory Courses: How They Help Students to Detect and Solve Systematic Errors

Abstract

Systematic errors are unfortunately common in analyses performed by students in teaching laboratories. Quality control (QC) tools are required to detect and solve bias in laboratory analyses.However, although QC has become routine in real-world laboratories, it is still rarely applied in 10 teaching laboratories. For this reason, systematic errors in students' results remain unknown in many cases. In this study, the use of control charts and critical thinking methodologies are applied in laboratory lessons to show students how the control charts can be used to detect and correct systematic biases in analyses. Students practice how to evaluate out-of-control results by applying scientific critical thinking procedures based on knowledge acquired in previous subjects, aiming to 15 find the source of the bias detected, solve it, and apply rectifying measures to improve the operational procedure. With the proposed methodology, students understand the importance of control charts in demonstrating the quality and validity of the data obtained. During the academic years applying this methodology, the most common source of bias was found to be related to an incorrect application of basic laboratory skills, which shows that these skills need to be learned and, most importantly, put 20 into practice over the whole period of student training and cannot be taken for granted once they have been taught in the early stages of their curricula. The learning outcomes were assessed through an exercise that requires students to evaluate results obtained in the laboratory in previous years. It was found that the majority of students (97.6%) were able to detect a bias, find the source, and solve the error.

Are basic laboratory skills adequately acquired by undergraduate science students? How control quality methodologies applied to laboratory lessons may help us to find the answer

“…Despite laboratory instructors having a strong suspicion of a skills deficit, which was observed in some cases during the laboratory sessions, it was not possible to assess the source of the errors as the students' reports were handed in at the end of the term and no feedback was possible. Therefore, it was decided to introduce a seminar about control charts at the end of the laboratory sessions to discuss with students their results and to try to find the sources of their non-conforming results [32].…”

“…In the case of the Biotechnology students, a seminar was introduced at the end of the laboratory sessions after the third year of this study to assess together with the students the quality of the results reported and discuss the possible sources of their non-conforming results [32]. A detailed assessment of the experimental procedure that the students followed was made using their quality control results, through the revision of their laboratory notebooks and by interviewing them.…”

Revisiting Chemophobia through a Social Justice Lens

“…Pedagogical strategies for supporting the development of critical thinking skills in chemistry have included: solving real-world problems; inquiry-based practicals; − games; writing exercises; − scaffolded peer feedback; guided critique; and pre- and postlearning activity quizzes . Similarly, methods to develop chemical literacy often aim to link apparently abstract and theoretical chemistry concepts to their applications in learners’ lives: context-based approaches, storytelling, discussing socio-scientific issues, problem-based learning, and inquiry-based learning have all received attention in the literature. ,− Some researchers have suggested that using the chemistry literature could be an approach to developing learners’ chemistry literacy, but this is much more common in higher-level courses compared to introductory teaching. , This leaves people who do not want to participate in high-level chemistry education unsupported in developing their chemical literacy and critical thinking skills in chemistry, disadvantaging many learners.…”

Portraying Critical and Creative Thinking Skills of Chemistry Teachers Candidate in Biochemistry Laboratory Activity

“…Critical thinking skills and creative thinking skills are significant aspects of HOTS in science learning [2][3][4]. Both of these abilities have been sought to be added to science education, either through curriculum integration or learning innovation.…”

“…Many previous studies on critical and creative thinking skills in chemistry and biochemistry laboratory activity have been carried out. Previous research has indicated that critical and creative thinking skills are not developed simultaneously in biochemistry laboratory DOI 10.18502/kss.v9i8.15661 ICMScE activity including: Sanchez developed and used control charts as a tool to analyze and validate student laboratory activity results so that they can detect and correct errors by critical thinking [3]. The use of laboratory activity modules designed for students during the COVID-19 pandemic can provide opportunities for them to practice research-relevant skills such as finding primary literature sources, creating test samples, explaining unexpected experimental results, and revising experimental procedures to improve methodology.…”