It is with sadness that we received the message that Karel Maršál passed away on March 6, 2023. Karel Maršál, MD, PhD, Professor Emeritus at Lund University and Director of the WHO Collaborating Center in Lund, was born in Prague, former Czechoslovakia, in 1943. After completing his undergraduate studies at Charles University in Prague, he and his fiancée Lida moved as political refugees to Sweden in 1968. They came to Malmö General Hospital in 1973, where Karel gained his specialty in obstetrics and gynecology. Already then, Malmö was a nursery for research on fetal physiology and monitoring, and Karel was soon involved. He defended his PhD thesis, “Ultrasonic Measurements of Fetal Breathing Movements in Man”, at Lund University in 1977. With the introduction of Doppler ultrasonography to measure blood flow velocity, an era of prolific research commenced, leading to a growing international collaboration under Karel's leadership. In a series of PhD theses, normal fetal circulation was mapped to form the basis for the clinical assessment of the compromised fetus, and for studying the effects of medications and smoking during pregnancy. Experimental work on fetal lambs added further insights into circulatory pathophysiology. The introduction of routine ultrasound in Malmö in 1972 paved the way for identifying and studying fetal growth restriction and its underlying circulatory changes, today a major clinical field. Karel was the Head of the Perinatal Division at the University Hospital in Malmö and his personality as an enthusiastic, persevering, and meticulous scientist earned him a professorship in Malmö in 1991. In 1997, Karel moved to Lund to become Professor in Obstetrics and Gynecology, and later head of the clinical department. In 1995, he became Honorary Professor at Charles University in Prague, Czech Republic. He also served as Director of the undergraduate program of the Medical School at Lund University and as Chief Medical Officer in the county of Skåne, Sweden. Karel was the main tutor of 21 PhD students and co-tutor of another 14 research students. He published 354 original papers, 132 book chapters and reviews, and 14 textbooks. He was editor or co-editor of the Journal of Maternal and Fetal Investigation, of Fetal and Maternal Medicine Review, and of Seminars in Fetal and Neonatal Medicine, and was a member of the editorial board of 10 international scientific journals. His primary areas of experience and research were in perinatology, obstetrics, fetal monitoring, obstetric and gynecologic ultrasound, Doppler ultrasound, fetal physiology, ultrasound safety, and obstetric quality assurance. Throughout the years, Karel's research was supported by numerous grants, among them from the prestigious Swedish Research Council. He was the principal investigator in numerous national and international multicenter studies, such as the EXPRESS study on extremely preterm infants in Sweden, and he was national coordinator for Sweden in three EU studies. Karel served as president of the International Society of Ultrasound in Obstetrics and Gynecology, he was an honorary member of various national and international institutions and a board member of European Federation of Societies for Ultrasound in Medicine and Biology, World Federation for Ultrasound in Medicine and Biology, and other societies. In the past, he was the main organizer of 15 international scientific congresses, including two world congresses on ultrasound in obstetrics and gynecology. He received several prestigious awards, such as the Ian Donald Gold Medal and the Haackert Gold Medal in Prenatal Medicine. Karel was elected Doctor Honoris Causae at universities in Olomouc, Czech Republic, and Poznan, Poland. He was course leader of 38 national and international postgraduate courses in perinatal medicine, obstetrics, ultrasound, and obstetric Doppler ultrasound. His last participation in such an event was in February 2023. Karel's wife, Lida, gave him unending support throughout his career. Had Karel not injured his leg in a skiing accident, their paths may never have crossed. He had to take a break from medical school, and when he returned to his studies, he and Lida became classmates. Innumerable mothers and children all over the globe have benefited from Karel's ground-breaking scientific work, leadership, and deeds. His 50-year career as a clinician, scientist, teacher, coach, role model, and—most of all—the best friend of the unborn baby is now at an end. Among his friends and co-workers, he will be vividly remembered as a quietly jovial, sharp-witted gentleman with a human perspective and a friendly attitude toward each of us. He is sorely missed.

Ultrasound in Obstetrics & GynecologyVolume 14, Issue 1 p. 9-11 OpinionFree Access Ultrasound dating of pregnancy – still controversial? P.-H. Persson, P.-H. Persson Cura Kliniken Malmö, SwedenSearch for more papers by this author P.-H. Persson, P.-H. Persson Cura Kliniken Malmö, SwedenSearch for more papers by this author First published: 23 December 2002 https://doi.org/10.1046/j.1469-0705.1999.14010009.xCitations: 6AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Citing Literature Volume14, Issue1July 1999Pages 9-11 RelatedInformation

AIM To study the detection rates of second trimester ultrasound screening for neural tube defects (NTD), abdominal wall defects (AWD) and Down's syndrome (DS) in low risk populations at tertiary centers, and to compare the ultrasound screening detection rates with those that were obtainable by biochemical serum screening (double test: alpha-fetoprotein/human chorion gonadotrophin/age test). STUDY DESIGN Prospective multicenter study with a three year inclusion period: 1/1/1989-31/12/1991. SUBJECTS 27,844 low-risk women at 18-34 years of age who had a second trimester ultrasound screening examination. Of these, 10,264 also had a serum test. METHODS An ultrasound malformation scan and a serum test were carried out at 17-19 weeks of gestation. Risk calculations regarding DS were based on alpha-fetoprotein, human chorion gonadotrophin and maternal age; performed retrospectively for the first two years. RESULTS In total 73 cases were identified in the study population: NTD (n=34), AWD (n=7) and DS (n=32). The detection rates, (%, with 95% confidence interval) for ultrasound screening were: NTD: 79.4 (62.1-91.3); AWD: 85.7 (42.1-99.6); DS: 6.3 (0.8-20.8). In the subgroup of women who had both tests, the detection rates for ultrasound screening vs double test were: NTD: 62.5 (24.5-91.5) vs 75.0 (34.9-96.8); AWD: 66.7 (9.4-99.2) vs 100 (29.2-100.0); DS: 7.7 (0.2-36.0) vs 46.2 (19.2-74.9). The false positive rates (%) for ultrasound screening vs double test were: NTD: 0.01/3.3; AWD: 0.01/3.3; DS: 0.1/4.0. CONCLUSION Second trimester ultrasound screening in a low risk population gave a low detection rate for fetal DS (6.3%) and an acceptable detection rate for NTD (79.4%) and AWD (85.7%). In the subgroup of women who had both tests, serum screening performed better than ultrasound as applied in the present study, especially regarding DS.

Available standard intrauterine growth curves based on birthweights underestimate foetal growth in preterm period. New growth curves are presented based on data from four Scandinavian centres for 759 ultrasonically estimated foetal weights in 86 uncomplicated pregnancies. Mean weight of boys exceeded that of girls by 2‐3%. A uniform SD value of 12% of the mean weight was adopted for the standard curves as the true SD varied non‐systematically between 9.1 and 12.4%. Applied to an unselected population of 8663 singleton births, before 210 days of gestation, 32% of birthweights were classified as small‐for‐gestational age (SGA; i.e. below mean ‐2SD); the corresponding figures were 11.1% for gestational ages between 210 and 258 days, and 2.6% for ages of 259 days or longer. The new growth curves reveal better the true distribution of SGA foetuses and neonates, and are suggested for use in perinatological practice.

In a prospective study during 1 year, 102 women with prolonged pregnancies (more than 294 completed gestational days) were followed with serial pulsed Doppler blood flow examinations every 2nd day, either to spontaneous onset of labor (n = 82) or to induction of labor due to subsequently occurring complications (n = 20). Mean aortic blood velocity did not change significantly with gestational age beyond 294 days either in fetuses with normal outcome or in fetuses that developed asphyxia at birth. The flow velocity waveforms in the descending aorta, the umbilical artery, the common carotid artery and the uterine artery did not change significantly compared to the values at term. Abnormal flow velocity waveforms in the fetal descending aorta, umbilical artery or uterine artery had no significant relationship to fetal asphyxia. Absence of diastolic flow velocities was not found in any of the vessels examined, indicating that the fetuses did not suffer from chronic hypoxia in utero and that aging of the placenta did not alter fetal and uteroplacental blood flow. Notching of the aortic flow velocity waveform was a common finding among prolonged pregnancies. The hemodynamic implications and consequences of this phenomenon are discussed.

Acta Obstetricia et Gynecologica ScandinavicaVolume 70, Issue 4-5 p. 405-406 Duration of human singleton pregnancy Points for discussion Reynir T. Geirsson, Reynir T. Geirsson Department of Obstetrics and Gynecology, National University Hospital, 101, Reykjavik, IcelandSearch for more papers by this authorPer-Håkan Persson, Per-Håkan Persson Cura clinic Erikslust, S-200 74, Malmo, SwedenSearch for more papers by this authorKarel Maršál, Karel Maršál Department of Obstetrics and Gynecology Malmö, General Hospital, S-214 01, Malmö, SwedenSearch for more papers by this author Reynir T. Geirsson, Reynir T. Geirsson Department of Obstetrics and Gynecology, National University Hospital, 101, Reykjavik, IcelandSearch for more papers by this authorPer-Håkan Persson, Per-Håkan Persson Cura clinic Erikslust, S-200 74, Malmo, SwedenSearch for more papers by this authorKarel Maršál, Karel Maršál Department of Obstetrics and Gynecology Malmö, General Hospital, S-214 01, Malmö, SwedenSearch for more papers by this author First published: January 1991 https://doi.org/10.3109/00016349109007905AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume70, Issue4-5January 1991Pages 405-406 RelatedInformation

Acta PaediatricaVolume 78, Issue 4 p. 633-634 Thyroid Gland Volume as Measured by Ultrasonography in Healthy Children and Adolescents in a Non-Iodine Deficient Area S. A. Ivarsson, S. A. Ivarsson Department of Pediatrics Obstetrics and Gynecology and Internal Medicine Malmö General Hospital University of Lund S-21401 Malmo SwedenSearch for more papers by this authorP.-H. Persson, P.-H. Persson Department of Pediatrics Obstetrics and Gynecology and Internal Medicine Malmö General Hospital University of Lund S-21401 Malmo SwedenSearch for more papers by this authorU.-B. Ericsson, U.-B. Ericsson Department of Pediatrics Obstetrics and Gynecology and Internal Medicine Malmö General Hospital University of Lund S-21401 Malmo SwedenSearch for more papers by this author S. A. Ivarsson, S. A. Ivarsson Department of Pediatrics Obstetrics and Gynecology and Internal Medicine Malmö General Hospital University of Lund S-21401 Malmo SwedenSearch for more papers by this authorP.-H. Persson, P.-H. Persson Department of Pediatrics Obstetrics and Gynecology and Internal Medicine Malmö General Hospital University of Lund S-21401 Malmo SwedenSearch for more papers by this authorU.-B. Ericsson, U.-B. Ericsson Department of Pediatrics Obstetrics and Gynecology and Internal Medicine Malmö General Hospital University of Lund S-21401 Malmo SwedenSearch for more papers by this author First published: July 1989 https://doi.org/10.1111/j.1651-2227.1989.tb17951.xCitations: 28AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. REFERENCES 1 Brunn J, Block U, Ruf G, Bos I, Kunze WP, Scriba PC. Volumetrie der Schilddrüsenlappen mittels Real-time Sonographic. Dtsch Med Wochenschr 1981; 106: 1338–40. 2 Gutekunst R, Smolarek H, Hasenpusch U et al. Goitre epidemiology: thyroid volume, iodine excretion, thyroglobulin and thyrotropin in Germany and Sweden. Acta Endocrinol 1986; 112: 494–501. 3 Hegediis L, Perrild H, Poulsen LR et al. The determination of thyroid volume by ultrasound and its relationship to body weight, age and sex in normal subjects. J Clin Endocrinol Metab 1983; 56: 260–63. 4 Berghout A, Wiersinga WM, Smiths NJ, Touber JL. Determinants of thyroid volume as measured by ultrasonography in healthy adults in a non-iodine deficient area. Clin Endocrinol 1987; 26: 273–80. Citing Literature Volume78, Issue4July 1989Pages 633-634 ReferencesRelatedInformation

In 22 patients with suspected diffuse goiter, the diagnostic accuracy of ultrasonography was compared with that of aspiration biopsy cytology and thyroid antibody testing. Ultrasonography was abnormal in 100% (10/10) of the patients with autoimmune thyroid disease, only 90% (9/10) of whom were identified with antibody testing. All patients with diffuse colloid goiter had normal echo patterns on ultrasound imaging, whereas 29% (2/7) of them had positive results on antibody testing. Whether these are 'false positives' or represent focal thyroiditis remains unclear. Thus, ultrasound imaging stands out as a valuable diagnostic tool for the differential diagnosis of diffuse thyroid disorders in children.

Based on routine fetometry screening at 32 weeks of gestation, 80 out of 3226 singleton pregnancies were suspected of intrauterine growth retardation (IUGR) and 72 of them were subjected to repeated fetal blood flow measurements by Doppler ultrasound for evaluation of the fetal condition. The maximum blood velocity wave form recorded from the fetal descending aorta and umbilical artery was classified as normal or abnormal depending on the presence or absence of positive end‐diastolic blood flow. Compared to the pregnancies with normal fetal blood flow, the group of 30 pregnancies with abnormal blood flow patterns had significantly more pregnancy complications and more operative deliveries for fetal distress. In the latter group, all newborns but one were small‐for‐gestational age and had low 1‐min Apgar scores more frequently. Fetal blood flow measurements have a good capacity for predicting unfavorable fetal outcomes and can be recommended for clinical use. The combination of ultrasound screening and Doppler blood flow measurement has reduced the number of pregnancies requiring intensive surveillance.

To analyse the incidence of fetal growth retardation and its impact on perinatal mortality and neonatal morbidity, pregnancies complicated by intra‐uterine growth retardation (IUGR) were compared with matched non‐IUGR pregnancies. The IUGR group included all infants born in the city of Malmö during the study period and having a birthweight of 2 standard deviations or more below the mean birthweight for gestational age. The gestational age of all pregnancies was assessed with ultrasound in the first half of pregnancy. The IUGR fetuses were more vulnerable during delivery, and emergency cesarean section due to imminent fetal asphyxia was performed more frequently, but Apgar scores were similar in both groups. The frequency of respiratory disorders was lower in the IUGR group than in the non‐IUGR group when corticosteroid‐treated pregnancies were excluded. The IUGR group required slightly longer care on the neonatal ward than the non‐IUGR group, but not more intervention. The IUGR group as a whole had an unexpectedly low neonatal complication rate, such complications as did occur being related to preterm birth rather than to growth retardation.

The cord thyroglobulin (Tg) concentration was estimated in 160 full-term newborns of whom 103 were delivered normally, 26 by elective Ceasarean section and 31 by vacuum extraction. There was no correlation between the median cord Tg concentration and gestational age at delivery (37–43 weeks), birth weight or sex of the child or the median cord TSH concentration. The median cord Tg concentration was significantly higher in the children born by Ceasarean section than in those delivered by vacuum extraction (P<0.001). The same tendency was found when smokers and non-smokers were compared separately. Mechanical force on the thyroid gland during labour and delivery therefore does not seem to increase the cord Tg concentration.

Dehydroepiandrosterone sulphate, progesterone, estradiol, estriol and human placental lactogen (hPL) were biochemically assayed in a group of 92 pregnancies in which intra-uterine growth retardation was suspected. The group was selected with ultrasound fetometry at 32 weeks of gestation, and maternal blood was sampled at 33, 35, 37 and 39 weeks of gestation. The IUGR group consisted of 30 pregnancies resulting in the birth of an infant with a birthweight of 2 standard deviations or more below the mean for gestational age in the Malmö population. Intra-uterine growth trends were defined by serial ultrasound fetometry performed every second week. Both serum hormone and hPL content were examined in relation to birth-weight, occurrence of imminent asphyxia at delivery, Apgar score, and pH in the umbilical vein. Neither dehydroepiandrosterone sulphate, nor progesterone nor estradiol values correlated to any of the outcome variables. To some extent estriol values distinguished IUGR from non-IUGR fetuses but not until the 39th gestational week, whereas hPL was effective in this respect in all weeks studied. An hPL value below 4 mg/l predicted IUGR with a sensitivity ranging from 52% to 74%, and a specificity ranging from 85% to 78%. HPL correlated well with the subsequent intra-uterine growth rate, but not with the outcome variables studied.

A noninvasive pulsed Doppler ultrasound technique was used to characterize blood flow in the descending thoracic aorta and the intra-abdominal part of the umbilical vein in 159 fetuses suspected of intrauterine growth retardation (IUGR) on the basis of ultrasound fetometry. From this group, 74 infants with IUGR (defined as gestational age-related birth weight of 2 standard deviations [SD] or more below the population mean) were born. The blood flow results were not available to the clinicians managing the pregnancies. Blood flow mean velocity in the fetal aorta was lower, pulsatility index and rising slope higher, and umbilical volume flow and umbilical flow per 100 g placental tissue were lower in the pregnancies with IUGR than in 21 normal pregnancies. The waveform of the maximum aortic velocity envelope was related to operative delivery for fetal distress, Apgar score, and umbilical cord blood pH. The pulsatility index and the configurational assessment of the diastolic part of the waveform were combined to form a new concept, the blood flow class. The blood flow class was abnormal in 57% of the fetuses classified as having IUGR at birth and in 93% of those growth-retarded fetuses who subsequently developed signs of fetal distress requiring operative delivery. Waveform analysis, in terms of blood flow class, seems to be a useful tool in the surveillance of fetuses when IUGR is suspected. Abnormal blood flow class is a marker of fetal distress and probably gives an earlier indication than antenatal nonstressed cardiotocography. The results of this study point to a strong association between IUGR and impaired fetal blood flow. The aortic volume blood flow, unlike waveform analysis, does not seem to be a variable sensitive enough to predict fetal outcome in the individual pregnancy.

A prospective study was made to evaluate whether bedrest in hospital is beneficial in pregnancies where intrauterine growth retardation (IUGR) was suspected. Diagnosis was based on routine fetometry at 32 weeks of gestation, in conjunction with general ultrasound screening. 107 patients with suspected IUGR‐pregnancies were divided into two groups, 49 in a hospital bedrest group and 58 in an ‘outpatient’ group. Fifteen women in the bedrest group refused hospitalization, and 8 women in the out‐patient group had to be hospitilised for medical reasons other than suspected growth retardation, leaving 79% of the women in their allocated group. The women in the bedrest group were hospitalized for a mean duration of 29.2 days (range 5‐54). The results suggest that bedrest in hospital is not beneficial, either to fetal growth or to pregnancy outcome.

The efficacy of fetal blood flow assessment in predicting fetal outcome was evaluated in 159 pregnancies suspected of intrauterine growth retardation (IUGR). Blood flow in the fetal aorta and umbilical vein was measured with imaging and pulsed Doppler ultrasound. Volume blood flow values and variables describing the waveform of the maximum aortic blood velocity were checked for relations to subsequent fetal outcome. A new semi-quantitative velocity waveform variable, blood flow class (BFC), was designed and tested. The occurrence of IUGR, imminent fetal distress, a low Apgar score at 1 and 5 min, and a low pH in the umbilical artery and vein were adopted to characterize fetal outcome. Receiver operating characteristic curves were used to demonstrate the sensitivity and false positive rate, and the Cohen's Kappa index was used to compare the predictive capacity of the various blood flow variables. BFC, describing the blood velocity waveform with emphasis on its end-diastolic part, was found to be the most powerful marker of imminent fetal asphyxia (Kappa = 0.66) and of intrauterine growth retardation (Kappa = 0.48).

Intra‐uterine growth retardation (IUGR) is a major problem in contemporary obstetrics. Early antenatal diagnosis is important if morbidity and mortality are to be minimized. We present the results of one years ultrasound fetometric screening for IUGR of the pregnant population in the city of MalmO. All pregnancies were dated by early bi‐parietal diameter (BPD) measurement. From findings at 32 weeks of gestation, an IUGR risk‐group (n =436) was selected on the basis of predicted birthweight deviations with reference to standard curves, established at the Department, for BPD, abdominal diameter, femur length, and intra‐uterine weight, all plotted against gestational age. The risk‐group, which included 60 (77%) of the 78 IUGR infants eventually born, was subjected to additional fetometry examinations at 34, 36 and 38 weeks of gestation, in the total pregnant population of 2068, each pregnancy was the subject of 2.3 examinations. Other fetometry variables were evaluated for their efficacy as IUGR markers, but were not found to be superior to the current screening procedure in which BPD and abdominal diameter are combined in a simple formula to assess intra‐uterine growth. Overall, the screening procedure currently used at Malmd had a sensitivity of 64.1% and a specificity of 96.5%, the prevalence for IUGR being 3.8%.

The capacity of a general ultrasound screening program to detect fetal malformations affecting the urinary tract was evaluated in an epidemiologic study. A total of 11,986 pregnant women, representing 97% of the pregnant population in Malmö, Sweden, from April 1978 through August 1983 were examined. On routine examinations performed by midwives in the 17th and 33rd gestational weeks, the fetal anatomy was carefully surveyed. The overall frequency of fetal malformations was 0.5%, with urinary tract abnormalities representing approximately 50% of the total number. In 20 of 33 cases, the ultrasound findings were those of hydronephrosis or hydroureter. In ten cases, a cystic renal malformation was found, and the remaining three cases represented double renal pelvis, Potter syndrome, and posterior urethral valve. A total of 28 abnormalities were unilateral and five bilateral. No case of unilateral absence of renal tissue was noted prenatally. Prenatal diagnosis of urinary tract abnormalities known to precipitate neonatal urosepsis and subsequent renal scarring and other complications makes it possible to start an early antibiotic prophylaxis regimen. A complete workup of the infants can be started early and before life-threatening complications occur.

ABSTRACT. 222 consecutive fetuses found by ultrasound to be in breech presentation in the 33rd gestational week were followed with repeated examinations in weeks 35 and 38. Ninety‐one of these fetuses persisted in breech presentation until delivery, while cephalic version occurred in 131. The frequency of hip joint instability was 21% in the breech delivered group and 1.5% in the vertex delivered group. The position of the fetal legs was established at each ultrasound examination. The intrauterine fetal attitude was classified as extended when the fetuses had extended knees and maximally flexed hips at all ultrasound examinations. This occurred in 30 breech delivered fetuses, 47% of which developed hip joint instability. Only 8% of the breech born infants with flexed legs in utero developed hip joint instability. It is concluded that instability of the hip joint is a consequence of the intrauterine attitude, rather than of the breech delivery per se.

Using multiple regression analysis, a formula was evolved for estimating fetal weight in utero , based on fetal biparietal diameter (BPD), abdominal diameter (AD) (mean of two orthogonal readings), and femur length (FL), measured by ultrasound within 48 hours before delivery or legal abortion in a stratified sample of 89 pregnancies, approx. 10 in each 500‐g weight class up to 5000 g. Tested on 135 neonates of varying birth weights, the formula evolved, wt = BPD 0.972 × AD 1.743 × FL 0.367 × 10 −2.647 , neither under‐nor over‐estimated weight in any weight class, the error in estimates having a standard deviation of 7.1%, and maximum error being 18%' of true weight. to establish an intra‐uterine growth curve, the formula was applied to 177 longitudinal measurements in 19 normal pregnancies; the estimated weight against gestational age (GA) curve so obtained best fitted a third‐degree equation, wt = 1443.4–32.32 × GA + 0.203 × GA 2 ‐0.000215 × GA 3 (r 2 = 0.978), tallying closely with the birth weight curve obtained in the same population from 4 743 pregnancies where gestational age had been assessed by ultrasound in early pregnancy. the present two growth curves, based on fetometry and on birth weight, differ from previous curves used almost universally by pediatricians.