Overnight urine samples

Based on EHES Manual, Part B. Fieldwork procedures, 2nd edition, 2016 Available at: http://urn.fi/URN:ISBN:978-952-302-701-5 These slides can be used freely, translated and adapted to national use (e.g. concerning the equipment). However, it is important to keep in mind that no changes should be made to the measurement techniques, which need to be standardized.

Exclusion criteria Overnight urine sample is not collected from participants with any condition that would make urine collection difficult with menstruation who refuse Reasons for exclusion are recorded.

Pregnant participants Results may need to be analyzed separately from those of other participants. Pregnancy should be recorded.

Overnight urine sample collection The participant collects the sample at home The sample needs to be brought back to the examination site or picked up from the participant’s home. The urine passed before going to bed is discarded, but all urine voided during the night is collected, including the first morning void.

Equipment for collection Plastic beaker with lid for voiding, 1000 ml for collection and storage before delivery of the sample

Equipment for processing and storage Pipet Stirring rod, plastic Plastic storage tubes, e.g. 3 ml storage tubes Cryo vials must be used if stored at -70°C or colder. Storage box for plastic tubes / cryo vials Freezer

Instructions to the participants (1) Give the participant A labelled 1000 ml plastic beaker for collection and storage of urine written instructions on collection of overnight urine sample sample collection recording form (also called laboratory form)

Instructions to the participants (2) Instruct the participant to empty the bladder and discard the urine before going to bed. The date and exact time are recorded in the sample collection recording form. All urine voided during the night, including the first morning void, is collected into the container. The last void is collected when 8 hours have elapsed from start of collection, just after rising up from the bed.

Instructions to the participants (3) As the time should encompass 8 hours, the participants should ideally be advised to go to bed at for example 10 pm or 11 pm and rise up at 6 am or 7 am, respectively. The exact time when the collection was ended is recorded in the sample collection recording form.

Instructions to the participants (4) Storing of the sample: The urine sample is stored in the container at room temperature sheltered from direct sunlight. The urine must not be frozen (under 0°C) before processed by survey personnel.

Instructions to the participants (5) Delivery of the sample: Instruct the participant to either deliver the sample to the examination site or laboratory, or agree on a schedule of picking the sample up from the participant’s home (according to the study protocol).

Sample delivery When the participant returns the sample, check the sample collection recording form with him/her. Record the time and date, when the sample was delivered, in the sample collection recording form.

Processing of the sample Mix the sample well and measure or read the volume. Record the measured volume in the sample collection recording form. Transfer aliquots of 2 ml into storage tubes. Label the tubes and store at -20 ᵒC or -70 ᵒC. Preferably several aliquots are made for storage and future use. The remaining urine is disposed of.

Acknowledgements Slides prepared by: Laura Paalanen Photographs: Laura Paalanen Experiences and feedback from the EHES network have been utilized in the preparation of these slides Funding: Preparation of the slides is part of the activities of the EHES Coordinating Centre which has received funding from the EC/DG SANTÉ in 2009-2012 through SANCO/2008/C2/02-SI2.538318 EHES and Grand Agreement number 2009-23-01, and in 2015-2017 through Grand Agreement number 664691/BRIDGE Health

Disclaimer The views expressed here are those of the authors and they do not represent the Commission’s official position.