Assessment of centrifugation knowledge among medical laboratory personnel: a survey-based study

Abstract

Background

This survey study aims to evaluate knowledge of centrifuge operation and adherence to centrifugation protocols among laboratory personnel. These aspects are crucial in preventing pre-analytical errors. Additionally, the study seeks to assess the equipment infrastructure and staffing status within the participants' institutions.

Methods

The study involved 397 participants from various medical laboratories. A 16-item survey, using a 5-point Likert scale, was utilized to assess theoretical and practical knowledge of centrifuge operation. Two groups of subscales were developed, with one focusing on theoretical and practical knowledge and the other on pre-centrifugation, centrifugation, and post-centrifugation processes. Demographic data were collected, and the reliability of the survey was analyzed using Cronbach's alpha (0.94). Validity was assessed through factor analysis.

Results

The majority of participants were female (63%) and worked as laboratory technicians (72%). Approximately 71% had never received formal centrifuge training, and significant differences were observed between theoretical and practical knowledge, particularly among laboratory technicians (P < 0.001). Education level and job title also influenced knowledge scores (P < 0.001).

Conclusion

The developed survey scale demonstrated high reliability and validity, indicating its potential as a valuable reference for future studies assessing centrifugation competency and usage in laboratory environments. These findings underline the need for improved training programs to reduce pre-analytical errors and enhance overall laboratory performance.

Background

Centrifugation is an essential separation technique widely employed in the preparation of serum, plasma, and urine specimens, which constitute the majority of samples processed in contemporary medical laboratories for analytical purposes. Centrifuges utilize centrifugal force generated by rotational motion to separate particles within a sample based on their shape, size, and density. The effective operation of this device necessitates the integration of both theoretical understanding and practical skills. Numerous guidelines meticulously outline the protocols that must be adhered to during these procedures, which are predominantly performed manually by laboratory personnel [1, 2].

Centrifugation protocols, including pre-centrifugation sample holding times, the proper positioning of tubes, the accurate selection of centrifugation time and RCF (Relative Centrifugal Force) values, as well as maintaining the centrifuge’s internal temperature and ensuring device cleanliness and maintenance, are crucial for the integrity of laboratory processes. Non-compliance with these established guidelines can result in hemolysis, delayed clot formation, degradation of samples, and breakage of tubes, ultimately leading to potential laboratory accidents. Adherence to these protocols is essential to ensure the accuracy and reliability of analytical outcomes. As a pivotal component of the preanalytical phase, an understanding of the variables influencing centrifugation before, during, and after its application is essential to mitigate preanalytical errors [3].

The use of centrifuges is critical for laboratory personnel across all levels. Evaluating the theoretical and practical knowledge of employees in this area can be effectively achieved through structured surveys. These surveys serve as a diagnostic tool to identify knowledge gaps among staff and to inform the development of targeted training programs as needed. This methodology is integral to enhancing both the safety and operational efficiency of laboratory environments [4, 5].

Surveys are typically conducted using validated scales for reliability and validity. However, we were unable to find a specific survey scale dedicated to centrifuge operation in existing literature. Consequently, we designed a survey scale by adhering to established publication [6].

The aim of our study is to assess the knowledge and experiences of laboratory professionals regarding the use of centrifuges through a survey method. By analyzing the collected data with statistical approaches, we seek to uncover insights that can help reduce pre-analytical errors and ultimately enhance the efficiency of laboratory operations.

Additionally, assessing the availability of centrifuge equipment and staffing conditions within laboratory settings is crucial for understanding the broader context of training needs. Insufficient infrastructure or personnel shortages can limit access to proper centrifugation training and contribute to deviations from standardized protocols. By evaluating these factors alongside personnel knowledge and adherence to guidelines, this study provides a comprehensive perspective on both individual competency and systemic challenges that may impact laboratory education and performance.

This study contributes to the education and training of healthcare professionals by evaluating the theoretical and practical knowledge of laboratory personnel regarding centrifuge operation. By identifying gaps in adherence to centrifugation protocols, it provides insights into competence assessment and the need for structured training programs to enhance laboratory performance. The findings support the development of evidence-based education strategies aimed at improving procedural adherence, reducing pre-analytical errors, and ensuring laboratory quality and patient safety.

Methods

This study was conducted in accordance with the principles of the Declaration of Helsinki, with all procedural stages adhering strictly to these ethical guidelines. Ethical approval for the study was granted by the Ethics Committee of Başakşehir Çam and Sakura City Hospital, under reference number KAEK/31.01.2024.65. To evaluate processes related to centrifugation, a 16-item survey was developed, utilizing a 5-point Likert scale for responses, where scores ranged from 1 to 5. Items 13 and 14 were reverse-coded questions, and the calculations were performed after the responses were reversed. Using these items, we designed two separate groups of subscales. The first four items were designed to assess theoretical knowledge, while the remaining items were aimed at evaluating practical knowledge. At the same time the survey was structured into a second group of three subscales using the same items.; the first seven items assessed pre-centrifugation activities, the following four items evaluated actions during centrifugation, the final four items focused on post-centrifugation procedures. The survey instrument is detailed in Table 1.

Table 1.

Survey form

CENTRIFUGE OPERATION SURVEY IN MEDICAL LABORATORIES
What is your gender?	Male		Female
What is your age?	< 25	26–30	31–35	36–40			> 41
What is your education level?	High School	Associate degree	Bachelor's Degree	Master's Degree			Doctorate
How many years have you worked in your profession?	< 5 years	6–10 years	11–15 years	16–20 years			> 21 years
What is your title?	Laboratory Technician	Assistant Doctor	Medical Biochemistry Specialist	Academic			Other
What department do you work in?	Biochemistry Laboratory	Central Laboratory	Microbiology Laboratory	Emergency Laboratory			Blood Transfusion and Others
What is the role of the institution you work for?	Secondary Health Care Institution	Tertiary Health Care Institution	City Hospital	Other
Have you received formal training in centrifuge operation and maintenance?	yes		no
How many tubes do you centrifuge on average per day?	< 10		10–100			> 100
What types of centrifuges are installed in your laboratory? (multiple choices allowed)
Questions (Items) (Please choose the option closest to you from the answers below.)			Importance Scale
			Strongly Disagree	Disagree	Neutral		Agree	Strongly Agree
Theoretical, Pre-Centrifugation [A centrifuge is a device used in medical laboratories to separate components of samples such as blood or urine based on their shape, size, or density by using the centrifugal force generated by its rotational motion.]			1	2	3		4	5
Theoretical, Pre-Centrifugation [When a blood sample is centrifuged, the supernatant at the top of the tube is plasma or serum, while blood cells (such as erythrocytes, leukocytes) settle at the bottom as sediment.]			1	2	3		4	5
Theoretical, Pre-Centrifugation [RPM refers to the number of revolutions per minute, while RCF is used to determine how strong a centrifugal force the centrifuge is generating. RCF is expressed as multiples of gravitational force, and it depends on the centrifuge radius and RPM.]			1	2	3		4	5
Theoretical, Pre-Centrifugation [Settings should be adjusted based on RCF when using a centrifuge.]			1	2	3		4	5
Practical, Pre-Centrifugation [Blood samples should be allowed to clot for at least 30 min before being centrifuged for serum extraction in yellow or red cap tubes with gel separators.]			1	2	3		4	5
Practical, Pre-Centrifugation [Blood collection tubes should be stored in an upright position prior to centrifugation to prevent clot disruption.]			1	2	3		4	5
Practical, Pre-Centrifugation [Blood specimens should be maintained at room temperature prior to centrifugation]			1	2	3		4	5
Practical, Pre-Centrifugation [The speed and duration of centrifugation vary depending on the cap color of the tubes; the device should be adjusted according to the manufacturer's recommendations.]			1	2	3		4	5
Practical, Centrifugation [Tubes should be balanced by weight and placed opposite each other in the centrifuge; a counterbalance tube should be used for an odd number of tubes.]			1	2	3		4	5
Practical, Centrifugation [Centrifuge tubes should remain securely capped during operation to prevent aerosol contamination.]			1	2	3		4	5
Practical, Centrifugation [The centrifuge duration should be set according to the tube manufacturer's recommendations. The centrifuge should be allowed to stop completely before the lid is opened.]			1	2	3		4	5
Practical, Centrifugation [If an abnormal situation occurs during centrifugation, the lid should not be opened, and the power cord should not be unplugged. The device's stop button should be used to bring it to a halt.]			1	2	3		4	5
Practical, Post-Centrifugation [After centrifugation, any remaining clots in the serum or plasma should be removed with a suitable stick.]			1	2	3		4	5
Practical, Post-Centrifugation [Tubes with incomplete separation after centrifugation can be centrifuged again.]			1	2	3		4	5
Practical, Post-Centrifugation [Centrifuges require daily cleaning.]			1	2	3		4	5
Practical, Post-Centrifugation [Centrifuges should undergo regular maintenance, and the procedures should be documented.]			1	2	3		4	5

Reliability of the study was analyzed using Cronbach's alpha, while validity was evaluated through factor analysis [7]. Data distribution was assessed by analyzing kurtosis and skewness values [8]. For group comparisons, Student's t-test was employed for two groups, and ANOVA was used for more than two groups and Paired sample t-test was used to compare the subgroups according to the scales. with a significance threshold set at P = 0.05. The surveys were administered online through the Google Forms platform, and the resulting data were subjected to statistical analysis using the SPSS 20.0 software package.

We acknowledge the assistance of the GPT-4 AI language model by OpenAI for support with statistical analysis and drafting of this manuscript. All critical decisions and final revisions were performed by the human authors. No AI tool is credited as an author, adhering to submission guidelines.

Results

The distribution of the demographic data of the volunteers participating in the study, along with the other queried parameters, is presented in Table 2. This study surveyed 397 healthcare professionals involved in centrifuge operation, revealing key demographic and professional insights. The majority of participants were female (63%), with 35% aged over 41 years and 37.8% holding an associate degree. Most respondents were laboratory technicians (72.8%), and the biochemistry laboratory (64.5%) was the most common workplace. A notable finding was that 29% of participants had never received formal training on centrifuge operation, despite 63.4% processing more than 100 tubes daily.

Table 2.

Distributions according to variables

Gender				Male				Female
				146, 37%				251, 63%
Age	< 25			26–30		31–35		36–40			> 41
	55, %14			102, 26%		57, 14%		43, 11%			140, 35%
Education Level	High School			Associate degree		Bachelor's Degree		Master's Degree			Doctorate
	10, 2.5%			150, 37.8%		134, 33.7%		41, 10.3%			62, 15.6%
Years of Experience	< 5 years			6–10 years		11–15 years		16–20 years			> 21 years
	124, 31.2%			81, 20.4%		40, 10.1%		51, 12.8%			101, 25.5%
Title	Laboratory Technician			Resident		Medical Biochemistry Specialist		Academician (Dr. Instructor, Assoc. Prof., Prof.)			Other
	289, 72.8%			36, 9.1%		58, 14.6%		12, 3.1%			2, 0.4%
Department	Biochemistry Laboratory			Central Laboratory		Microbiology Laboratory		Emergency Laboratory			Blood Transfusion Center and Others
	256, 64.5%			83, 21%		43, 10.8%		8, 2%			7, 1.7%
Role of the Institution		2nd Level Health Institution			3rd Level Health Institution		City Hospital			Other
		89, 22.4%			140, 35.3%		166, 41.8%			2, 0.5%
Have you previously received training on centrifuge operation?				Yes				No
				282, 71%				115, 29%
Average daily number of centrifuged tubes			< 10			> 100			10–100
			90, 22.6%			252, 63.4%			55, 14%

Figure 1 illustrates the distribution of centrifuge types installed in participants' institutions.

Fig. 1.

The distribution of centrifuge types across institutions. This bar graph illustrates the number of institutions utilizing different types of centrifuges. The most commonly used centrifuge type is the swing-out rotor centrifuge - refrigerated, employed by 313 institutions (78.8%), followed by the swing-out rotor centrifuge - non-refrigerated, used in 227 institutions (57.2%). The fixed-angle centrifuge is utilized by 153 institutions (38.5%), while the ultracentrifuge is the least commonly used, present in 71 institutions (17.9%)

The responses to the survey items were converted into scalar variables by calculating the mean values of the items within the defined subscales, resulting in new computed values. Mean values for each item's responses were calculated for all participants. Additionally, the mean values for derived subscales were calculated and are presented in Table 3.

Table 3.

Mean scores of individual survey items and subscales assessing theoretical and practical knowledge of centrifuge operation. The table presents the mean scores for each survey item, categorized under two primary subscales: theoretical and practical knowledge. Additionally the table presents the mean scores for each survey item, categorized into three subscales: pre-centrifuge, centrifuge, and post-centrifuge phases

Item	Item mean score	Subscales Assessing Theoretical and Practical Knowledge		Subscales Assessing the Stages of the Centrifugation Process
Item 1	3.98	Theoretical	3.8073	Pre-centrifuge	3.7488
Item 2	4.10
Item 3	3.74
Item 4	3.40
Item 5	3.72	Practical	3.9605
Item 6	3.51
Item 7	3.79
Item 8	3.71			Centrifuge	4.0131
Item 9	4.17
Item 10	4.07
Item 11	4.05
Item 12	4.07
Item 13	4.49			Post-centrifuge	4.1121
Item 14	4.50
Item 15	3.44
Item 16	4.02

Reliability was assessed using Cronbach's alpha method, yielding a high value of 0.94, indicating strong internal consistency. Validity was evaluated through factor analysis, with the KMO value calculated at 0.95, and Bartlett's test also showed a significant result. These results suggest that the survey scale we developed is both reliable and valid for the intended measurements.

The results of the group comparisons for the evaluated variables are displayed in Table 4. It was determined that the primary contributing factors to the observed variances were educational level and title.

Table 4.

The P-values obtained through the appropriate statistical group comparison methods are presented in the table

	Pre-Centrifugation	Centrifugation	Post-Centrifugation	Theoretical	Practical
Gendera	0.26	0.77	0.24	0.38	0.39
Ageb	0.14	0.63	0.24	0.38	0.27
Education Levelb	< 0.001	0.005	0.04	< 0.001	< 0.001
Years of Experienceb	0.84	0.44	0.036	0.33	0.08
Titleb	< 0.001	< 0.001	0.018	< 0.001	< 0.001
Departmentb	0.78	0.54	0.91	0.73	0.81
Role of the Institutionb	0.51	0.78	0.58	0.45	0.72
Have you previously received training on centrifuge operation? a	0.99	0.75	0.41	0.82	0.96
Average daily number of centrifuged tubesb	0.159	0.198	0.008	0.15	0.08

^aStudent's t-test

^bANOVA

Comparison of Theoretical and Practical Knowledge (Subscales Evaluating Theoretical and Practical Competence): The average score for theoretical knowledge was calculated as 3.8073. There were significant differences in theoretical knowledge levels based on education level and job title. Participants with an associate or bachelor's degree had lower theoretical knowledge scores (P=0.007 and P<0.001, respectively). Practical Knowledge: The average score for practical knowledge was 3.9605. Education level and job title also showed significant differences in practical knowledge. There was a considerable gap between practical and theoretical knowledge, especially among laboratory technicians (P<0.001).

Comparison of Centrifugation Process Stages (Subscales Evaluating Pre-Centrifugation, Centrifugation, and Post-Centrifugation Knowledge: Pre-Centrifugation Knowledge: The average score in this area was 3.7488. Significant differences were found based on education level (P < 0.001) and years of experience (P = 0.036). During Centrifugation Knowledge: The average score for knowledge required during centrifugation was 4.0131. Significant differences were observed based on education level (P = 0.005) and job title (P < 0.001). Post-Centrifugation Knowledge: The average score for post-centrifugation knowledge was 4.1121. Education level (P = 0.04) and years of experience (P = 0.036) also showed significant differences.

In both groups, significant differences among laboratory technicians were observed in theoretical and practical knowledge subscales, while this difference was not noted in other job titles. This suggests that technicians have more pronounced deficiencies in theoretical than practical knowledge. Additionally, participants with lower educational levels had lower theoretical knowledge than practical knowledge.

To assess the impact of educational level in greater detail, a paired sample T-test was performed to determine if there was a significant difference between theoretical and practical knowledge. The results indicated a significant disparity among participants with an associate degree or bachelor's degree (0.007, < 0.001 respectively) where theoretical knowledge scores were notably lower. In contrast, no significant difference was observed among those with a master's degree or higher (0.26, 0.49 respectively). Interestingly, no significant difference was observed among participants who reported having a high school level of education. A similar comparison by title shows that there was a significant difference between theoretical and practical knowledge scores among laboratory technicians (P < 0.001), while no significant difference was observed among other participants (Resident (P = 0.59), Medical Biochemistry Specialist (P = 0.52), Academician (P = 0.93)).

Conclusion

Centrifugation is a crucial technique in medical laboratories used to separate samples, particularly serum and plasma and, to a lesser extent, urine, and other body fluids. It requires both theoretical knowledge and practical skills. Adhering to centrifugation protocols is vital to prevent pre-analytical errors and guarantee accurate and dependable results. Studies have revealed that deviations from recommended pre-centrifugation holding times adversely affect the levels of potassium (K +), phosphate (Pi), magnesium (Mg2 +), calcium (Ca2 +), iridium (Ir), lactate dehydrogenase (LDH), glucose (GLU), creatinine (CREA), blood urea nitrogen (BUN), and ferritin (FERR), as delineated in clinical guidelines [9, 10]. Furthermore, adherence to designated centrifugation times is crucial, as deviations have been shown to introduce significant biases in the measurements of ALT, calcium ions (Ca2 +), glucose (GLU), potassium ions (K +), blood urea nitrogen (BUN), and creatine kinase-MB (CK-MB) [11]. It has been documented that deviations from the prescribed internal temperature settings of centrifuges are associated with clinically relevant alterations in biochemical markers such as alanine transaminase (ALT), thyroid-stimulating hormone (TSH), and free thyroxine (fT4) [12]. Additionally, incorrect calibration of centrifuge speed and operation time has been linked to platelet activation [13]. The literature also indicates that centrifugation processes not conducted in accordance with established guidelines can result in hemolysis [14, 15]. Current knowledge regarding clot-related issues predominantly originates from research aimed at producing platelet-rich plasma, highlighting that variations in centrifugation conditions can alter the properties of the residual clot [16].

The majority of the issues reported in the literature are related to personnel-related causes. At this point, questioning the staff's theoretical and practical knowledge and developing solutions to address identified deficiencies would be an appropriate strategy. Surveys can be utilized to assess and enhance laboratory personnel's comprehension of medical practice procedures [17, 18].

Although there is no published data, it is believed that there are nearly two thousand medical analysis laboratories in Türkiye. Similarly, we have not been able to find published data regarding the demographic data of laboratory employees in these laboratories. We believe that the data we present in our study will contribute to the literature in this regard. According to the data obtained from our study, it is observed that the employees are predominantly female (63%) and young (49% under 30 years of age). The demographic data reported in other survey studies conducted in various countries involving laboratory professionals in the literature are consistent with the data from our own country [19–21].

Our survey findings indicate the widespread use of refrigerated swing-out rotor centrifuges in medical laboratories, emphasizing their critical role in routine sample preparation. These centrifuges are the recommended devices for this purpose [2]. Based on the survey data, it was observed that 78.8% of the medical laboratories where participants are employed have refrigerated swing-out rotor centrifuges in place. Ultracentrifuges, capable of reaching forces exceeding 100,000 g, are primarily used for analytical applications. However, centrifuges above 10,000 g in many medical laboratories, commonly employed to prepare lipemic samples, are erroneously called ultracentrifuges. Notably, only 17% of respondents reported the presence of ultracentrifuges in their laboratories, highlighting the discrepancy between actual ultracentrifuge operation and the misapplication of the term in practice.

The study reveals that demographic factors such as gender, age, departmental affiliation, and institutional background do not significantly impact overall scores or specific subscales. Interestingly, 71% of the participants reported not receiving formal training on centrifuge operation, showing a clear gap in education on this subject. Additionally, no noticeable differences were found between participants who had received training and those who had not. Significant differences were observed among laboratory technicians in both theoretical and practical knowledge subscales, while these differences were not noted in other job titles. This finding suggests that laboratory technicians have more pronounced deficiencies in theoretical knowledge compared to practical knowledge. Furthermore, participants with lower educational levels exhibited lower theoretical knowledge than practical knowledge. The data also reveal that participants' education level and professional title significantly affect their performance. Most participants were young individuals whose education was impacted by the Covid-19 pandemic. Several studies have highlighted the negative effects of the pandemic on practical training, and our findings suggest that age has a minor impact on skill acquisition in this context. [22–24]. Notably, laboratory technicians showed lower competencies in both theoretical and practical aspects compared to their colleagues, with notably lower levels of theoretical knowledge. It is evident that current in-service training programs on centrifuge operation need to be more effective in addressing these deficiencies. This highlights the challenge of delivering effective practical training, as targeted instruction on techniques such as centrifuge operation appears to only lead to expected improvements in proficiency among practitioners.

In conclusion, centrifuge operation training should be integrated into the curricula of educational programs that specifically train laboratory technicians, covering both theoretical and practical aspects. Additionally, more effective, and efficient post-graduation in-service training programs should be developed and implemented, considering published guidelines. The effectiveness of these training programs should be assessed through survey studies, and necessary revisions should be made based on the identified deficiencies. The survey we prepared to assess centrifuge operation, along with the reliability and validity of the scale we developed, is a valuable tool that can serve as a reference for future studies. Although the reliability and validity results of the scale were high, we believe that additional studies with more participants and data from different laboratory settings would be beneficial for the generalizability of the findings.

Limitations

This study has several limitations that should be considered when interpreting the findings. First, the study was conducted using a cross-sectional survey design, which limits the ability to establish causal relationships or assess changes in knowledge and practices over time. A longitudinal approach could provide more insight into the impact of training programs on centrifugation competence. Second, the reliance on self-reported data introduces the potential for response bias, as participants may overestimate their knowledge or provide socially desirable responses. Objective assessments, such as direct observation of centrifugation practices or standardized testing, would enhance the accuracy of knowledge and skill evaluation. Additionally, institutional differences in laboratory equipment, standard operating procedures, and workload variability may have influenced participants’ knowledge levels, limiting the generalizability of the findings to other settings. Furthermore, the study was conducted in a specific geographic region, and results may not fully reflect the practices and challenges faced by laboratory professionals in different healthcare systems or international settings. Despite these limitations, this study provides valuable insights into the gaps in theoretical and practical knowledge of centrifugation among medical laboratory personnel and highlights the urgent need for standardized training programs to enhance laboratory quality and patient safety.

Abbreviations

RCF

Relative Centrifugal Force

g

g-force" (gravitational force)

Authors’ contributions

Alper Gümüş: Conceptualization, survey scale design, data collection, statistical analysis, manuscript writing, supervision. Oğuzhan Zengi: Statistical analysis, manuscript writing, literature review. Cemal Kazezoğlu: Distribution of the survey, Data collection. Kamil Taha Uçar: Transferring the survey to the online platform, data debugging.. Cihan Coşkun: Statistical analysis, manuscript writing, literature review.. Semih Tek: Data collection, redaction. Nazife Doğan: Literature review, manuscript writing. Muhammed Emin Düz: Data collection, Corresponding supervision. Gülsen Şener: Data collection, redaction. Kübra Nur Köyüstü: Preparation of ethical committee application documents, monitoring of official procedures.

Funding

No financial support was received from any individual or institution for this study.

Data availability

No datasets were generated or analysed during the current study.

Declarations

Ethics approval and consent to participate

Ethical approval for the study was granted by the Ethics Committee of Başakşehir Çam and Sakura City Hospital, under reference number KAEK/31.01.2024.65. The informed consent was obtained from participants online by requesting their voluntary participation and providing the necessary information at the beginning of the survey.

Competing interests

The authors declare no competing interests.