====== Spirometry validation and reference values ====== Researchers from the [[https://www.rug.nl/staff/j.m.vonk/|University Medical Center Groningen]] performed a validation of the [[Pulmonary Function Test]] from participants at [[1a_visit_1|1A visit 1]] and [[2a_visit_1|2A visit 1]]. Additionally, reference values have been developed. ([[sections]]: [[physical state]] ([[Pulmonary Function Test]]) and [[secondary & linked variables]]).\\ The spirometry variables can be requested in the Lifelines catalogue or by mail (data@lifelines.nl).\\ ===== Validation ===== [[Pulmonary Function Test|Spirometry]] is performed according to Standard Operating Procedures using the Welch Allyn SpiroPerfect device. Judgment on technical correctness is performed by a Lifelines assistant, a pulmonologist, or both, according to a standard review procedure. Only data from pulmonary function tests that are judged to be technically correct should be used in the analyses. Technically correct is defined as: * Test performed according to ATS criteria or * Test not performed according to ATS criteria, but clinically reliable. In case both the pulmonologist and the Lifelines assistant judged the technical correctness, the priority is given to the judgment of the pulmonologist.\\ **Important:** part of the spirometry results have been listed as technically invalid, as a result the researchers from the UMCG recommend you to __NOT__ use these results in analyses.\\ === Validation rules === To select only technically valid measurements the following rules were applied: | **IF...** | **THEN...** | |Review specialist is "ATS" (1) or "Not ATS, clinically reliable" (2)|Spirometry is technically correct| |Review specialist is "Not ATS, not to assess" (3) |Spirometry is not technically correct| |Review specialist is missing or "No announcement" (0) and Review assistant is "ATS" (1) or "Not ATS, clinically reliable" (2)|Spirometry is technically correct| |Review specialist is missing or "No announcement" (0) and Review assistant is "Not ATS, not to assess" (3) |Spirometry is not technically correct| |Other case|Spirometry is not technically correct| ===== Reference values ===== Reference values based on age, height, and sex are calculated based on the Global Lung Function Initiative (GLI) using the [[https://www.ers-education.org/guidelines/global-lung-function-initiative.aspx|GLI provided syntax codes and databases]]. === Remarks UMCG researcher === * It is important to note that ethnicity has not been taken into account. Everyone has been treated as Caucasian. * There are a few adults subjects with a huge difference in height between [[1a_visit_1|1A visit 1]] and [[2a_visit_1|2A visit 1]] resulting in a huge difference in reference values. It is recommended to exclude the adult subjects with a height difference of more than 5 cm using the height variable.\\ ===== Article ===== * Mahon, G. M., Koppelman, G. H., & Vonk, J. M. (2021). Grandmaternal smoking, asthma and lung function in the offspring: the Lifelines cohort study. Thorax, 76(5), 441-447. DOI: 10.1136/thoraxjnl-2020-215232\\ ===== Variables ===== | **Label English** | **Label Dutch** | **Code** | **Variable** | **Assessment** | **Age** | | Technically valid spirometry? | Technisch correcte spirometrie? | spirometry_valid_all_c_1 | spiro_ok | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | predicted FEV1 value (liter) | voorspelde FEV1 waarde (liter) | fev1_predicted_all_c_1 | FEV1_predicted | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | predicted FEV1FVC value (liter) | voorspelde FEV1FVC waarde (liter) | fev1fvc_predicted_all_c_1 | FEV1FVC_predicted | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | predicted FVC value (liter) | voorspelde FVC waarde (liter) | fcv_predicted_all_c_1 | FVC_predicted | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | predicted FEF75 value (liter per second) | voorspelde FEF75 waarde (liter per seconde) | fef75_predicted_all_c_1 | FEF75_predicted | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | predicted FEF25_75 (liter per second) | voorspelde FEF25_75 waarde (liter per seconde) | fef2575_predicted_all_c_1 | FEF2575_predicted | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | z-score FEV1 value | z-score FEV1 waarde | fev1_zscore_all_c_1 | FEV1_zscore | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | z-score FEV1FVC value | z-score FEV1FVC waarde | fev1fvc_zscore_all_c_1 | FEV1FVC_zscore | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | z-score FVC value | z-score FVC waarde | fcv_zscore_all_c_1 | FVC_zscore | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | z-score FEF75 value | z-score FEF75 waarde | fef75_zscore_all_c_1 | FEF75_zscore | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | z-score FEF25_75 value | z-score FEF25_75 waarde | fef2575_zscore_all_c_1 | FEF2575_zscore | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | Lower limit of normal FEV1 (liter) | Ondergrens van normale FEV1 (liter) | fev1_lowerlimit_all_c_1 | FEV1_LLN | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | Lower limit of normal FEV1FVC (liter) | Ondergrens van normale FEV1FVC (liter) | fev1fvc_lowerlimit_all_c_1 | FEV1FVC_LLN | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | Upper limit of normal FEV1FVC (liter) | Bovengrens van normale FEV1FVC (liter) | fev1fvc_upperlimit_all_c_1 | FEV1FVC_ULN | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | Lower limit of normal FVC (liter) | Ondergrens van normale FVC (liter) | fvc_lowerlimit_all_c_1 | FVC_LLN | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | Lower limit of normal FEF75 (liter per second) | Ondergrens van normale FEF75 (liter per seconde) | fef75_lowerlimit_all_c_1 | FEF75_LLN | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | Lower limit of normal FEF25_75 (liter per second) | Ondergrens van normale FEF25_75 (liter per seconde) | fef2575_lowerlimit_all_c_1 | FEF2575_LLN | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | FEV1 % predicted | FEV1 % voorspeld | fev1_percpredicted_all_c_1 | fev1pp | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | FEV1FVC % predicted | FEV1FVC % voorspeld | fev1fvc_percpredicted_all_c_1 | fev1fvcpp | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | FVC % predicted | FVC % voorspeld | fvc_percpredicted_all_c_1 | fvcpp | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | FEF75 % predicted | FEF75 % voorspeld | fef75_percpredicted_all_c_1 | fef75pp | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | FEF25_75 % predicted | FEF25_75 % voorspeld | fef2575_percpredicted_all_c_1 | fef2575pp | [[1A visit 1|1A]] [[2A visit 1|2A]] | 18+ | | change in FEV1 2A versus 1A (liter per year) | verandering in FEV1 2A versus 1A (liter per jaar) | fev1_change_all_c_1 | dfev1 | [[2A visit 1|2A]] | 18+ | | change in FEV1FVC 2A versus 1A (liter per year) | verandering in FEV1FVC 2A versus 1A (liter per jaar) | fev1fvc_change_all_c_1 | dfev1fvc | [[2A visit 1|2A]] | 18+ | | change in FVC 2A versus 1A (liter per year) | verandering in FVC1 2A versus 1A (liter per jaar) | fvc_change_all_c_1 | dfvc | [[2A visit 1|2A]] | 18+ | | change in FEF75 2A versus 1A (liter per second per year) | verandering in FEF75 2A versus 1A (liter per seconde per jaar) | fef75_change_all_c_1 | dfef75 | [[2A visit 1|2A]] | 18+ | | change in FEF25_75 2A versus 1A (liter per second per year) | verandering in FEF25_75 2A versus 1A (liter per seconde per jaar) | fef2575_change_all_c_1 | dfef2575 | [[2A visit 1|2A]] | 18+ | | difference in body length adults 2A versus 1A | verschil in lichaamslengte volwassenen 2A versus 1A | spirometry_bodylength_all_c_1 | heightdifference_adults | [[2A visit 1|2A]] | 18+ |