Introduction:We hypothesized that patients are poorly informed about proper procedure for 24-hour urine specimen collection and its relevance in determination of biochemical analytes, despite availability of leaflets and webpage with instruction for collection. The aim of this survey was to question outpatients how well are they informed about procedure of 24-hour urine specimen collection.Materials and methods:The survey with 10 questions was done in outpatient laboratory of University Department of Chemistry, Medical School University Hospital Sestre Milosrdnice, Zagreb, Croatia. The study included 59 patients with collected 24-hour urine sample who have consented to participate in the survey.Results:Out of 59 participants, most of them (0.97) were older than 40 years. Internet was not recognized as a source of information (1/59). Almost one third of the patients have changed their drinking habits to collect more urine volume. Although most of the patients (0.60) were aware that the bottle of water is the best choice for the container, almost half of them were collected urine samples in the plastic soft drink bottle. Laboratory staff and physicians often have given information about proper collection procedure, but that information was insufficient.Conclusions:Patients are usually not aware of importance of proper preanalytical procedure for collecting urine specimen and how improper collection could affect results of requested tests. Education of outpatients, general practitioners and laboratory staff is needed in order to improve sample quality and trueness of results.

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Laboratory medicine is amongst the fastest growing fields in medicine, crucial in diagnosis, support of prevention and in the monitoring of disease for individual patients and for the evaluation of treatment for populations of patients. Therefore, high quality and safety in laboratory testing has a prominent role in high-quality healthcare. Applied knowledge and competencies of professionals in laboratory medicine increases the clinical value of laboratory results by decreasing laboratory errors, increasing appropriate utilization of tests, and increasing cost effectiveness. This collective paper provides insights into how to validate the laboratory assays and assess the quality of methods. It is a synopsis of the lectures at the 15th European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Continuing Postgraduate Course in Clinical Chemistry and Laboratory Medicine entitled "How to assess the quality of your method?" (Zagreb, Croatia, 24-25 October 2015). The leading topics to be discussed include who, what and when to do in validation/verification of methods, verification of imprecision and bias, verification of reference intervals, verification of qualitative test procedures, verification of blood collection systems, comparability of results among methods and analytical systems, limit of detection, limit of quantification and limit of decision, how to assess the measurement uncertainty, the optimal use of Internal Quality Control and External Quality Assessment data, Six Sigma metrics, performance specifications, as well as biological variation. This article, which continues the annual tradition of collective papers from the EFLM continuing postgraduate courses in clinical chemistry and laboratory medicine, aims to provide further contributions by discussing the quality of laboratory methods and measurements and, at the same time, to offer continuing professional development to the attendees.

Obtained results indicate that it is necessary to determine diagnostic accuracy of used dipstick in order to define purpose of urinalysis. It is very important to choose dipstick with ascorbic acid indicator and to examine ascorbic acid impact on dipstick analytes independently of manufacturer claims.

Manual handling of hemolyzed samples may lead to risk of errors in reporting results for troponin T, potassium and total bilirubin, which may have an effect on clinical decision. In addition, unnecessary suppression of the sample results unaffected by hemolysis could affect patient outcome.