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K S Khan

Publications and source records attributed to K S Khan.

At least 37 records · Page 2Linked to original sources
PubMed2005

Accuracy of fetal echocardiography in the routine detection of congenital heart disease among unselected and low risk populations: a systematic review.

OBJECTIVE: To determine among unselected and low risk populations the accuracy with which fetal echocardiography during the second trimester detects congenital heart disease. DESIGN: A systematic review of studies that assess the accuracy of fetal echocardiography. SETTING: District General Hospital and Tertiary referral centres. POPULATION: Women during the second trimester attending for ultrasound assessment. METHODS: General bibliographic databases (e.g. MEDLINE, EMBASE) and specialist computerised databases (e.g. Cochrane Library, National Research Register), grey literature, manual searching of reference lists of primary and review articles and personal contact with experts were used to identify studies. Studies were included if fetal echocardiography among unselected or low risk pregnant women was compared against a postnatal reference standard. Data were extracted on quality, study design and characteristics, and accuracy data to construct 2 x 2 tables. Data were synthesised qualitatively, and sensitivity and specificity with 95% confidence intervals were calculated. MAIN OUTCOME MEASURE: Sensitivity and specificity. RESULTS: Five primary studies met the inclusion criteria and comprised 60,901 subjects. One study assessed the accuracy of fetal echocardiography among an unselected population and four studies among low risk populations. All eligible studies found that fetal echocardiography helped to correctly diagnose normal fetus among unselected and low risk populations. Correct diagnosis of babies for congenital heart defects was higher among the unselected population (85%) than among the low risk populations (range from 35% to 86%); however, the potential for ascertainment bias and the choice of reference standard limits the validity of this finding. The variation in sensitivity across studies was not explainable by clinical factors such as scanning regime, operator skill and equipment. CONCLUSIONS: The evidence from this review about the accuracy of fetal echocardiography does not lend support to its routine use among unselected and low risk populations during the second trimester to detect congenital heart disease.

Echocardiography↗
PubMed2004

Accuracy of absence of fetal breathing movements in predicting preterm birth: a systematic review.

OBJECTIVE: To determine the accuracy with which the absence of fetal breathing movements on ultrasound examination predicts spontaneous preterm birth in women with threatened preterm labor. METHODS: Data sources included Medline, Embase, Pascal, Biosis, Cochrane Library, Medion, National Research Register, SciSearch, conference papers, and manual searching of bibliographies of known primary and review articles. A study was selected if it used absence of fetal breathing movements on ultrasound to predict spontaneous preterm birth in women with threatened preterm labor but before advanced cervical dilatation. Two reviewers independently selected studies and extracted data on their characteristics, quality and accuracy. Accuracy data were used to form 2 x 2 contingency tables with birth within 48 h and within 7 days of testing as the reference standards. Likelihood ratios for a positive test (LR+) and negative test (LR-) were calculated as a measure of accuracy. RESULTS: There were eight studies, which included a total of 328 women, evaluating the accuracy of absence of fetal breathing movements in predicting spontaneous preterm birth in women with threatened preterm labor. There were differences in the methodological quality among the included studies. All were lacking in one or more item that make up an ideal test accuracy study. For women presenting with threatened preterm labor, meta-analysis showed a summary LR+ of 14.80 (95% CI, 6.30-34.79) with a corresponding summary LR- of 0.46 (95% CI, 0.36-0.58) for predicting preterm birth within 7 days, and summary LR+ of 7.84 (95% CI, 1.12-54.99) and summary LR- of 0.25 (95% CI, 0.13-0.48) for predicting preterm birth within 48 h of testing. CONCLUSION: Absence of fetal breathing movements has the potential to be a useful test in predicting preterm birth both within 7 days and within 48 h of testing. However, the available studies were deficient in their sample size and quality of methodology. Future research should be undertaken to evaluate this technology and to address the methodological deficiencies.

Female↗
PubMed2004

Quality of life instruments in studies of chronic pelvic pain: a systematic review.

The use of quality of life (QoL) instruments in chronic pelvic pain (CPP) will allow a more objective assessment of patient-centred clinical outcomes. However, there is concern that not enough emphasis is placed on clinical face validity (i.e. issues which are of importance to patients and reflect their experiences and concerns). To explore this issue, we performed a systematic review of published research. Relevant papers were identified through electronic scanning of six electronic databases and by manual searching of bibliographies of known primary and review articles. Studies were selected if they assessed women with CPP for life quality, either developing QoL instruments or applying them as an outcome measure. Selected studies were assessed for the quality of their QoL instruments using a 17-item checklist, including 10 items for clinical face validity and seven items for measurement (psychometric) properties. A total of 19 articles were eligible for inclusion in the review. The generic Short Form 36 Health Survey Questionnaire (SF-36) was used most frequently, being employed in 10/19 (53%) of the studies. Three studies developed disease-specific QoL instruments for CPP complying with 59 - 77% of the quality criteria. Overall, quality assessment showed that only 4/18 (22.2%) studies complied with more than half the criteria for face validity, whereas 12/18 (66.6%) studies complied with more than half of the criteria for measurement properties (P = 0.0001). Among existing QoL instruments, compliance with the quality criteria for measurement properties is higher than for clinical face validity. There is a need to develop disease specific QoL instruments for CPP with face validity in addition to sound measurement properties.

Chronic Disease↗
PubMed2004

The accuracy of risk scores in predicting preterm birth--a systematic review.

This review aims to determine the accuracy with which published risk scores predict spontaneous preterm birth in pregnant women. Studies were identified without language restrictions through nine different databases (up to June 2002), and manual searching of bibliographies of known primary and review articles. Two reviewers selected studies independently and extracted data on their characteristics, quality and accuracy. Accuracy data were used to form 2 x 2 contingency tables of the results of risk scoring with spontaneous preterm birth as the reference standard. Heterogeneity was assessed and its reasons were explored. Summary estimates of accuracy were produced within clinically appropriate subgroups. There were 19 primary accuracy articles that met the selection criteria, including a total of 67390 women. There are 12 different risk-scoring systems, the one developed by Creasy being the most commonly evaluated. Quality features of an ideal study, such as blinding and consecutive enrolment, were frequently missing from the included studies, no study fulfilled all criteria for high quality study, and there was heterogeneity between their accuracy estimates. The reference standard most often used was birth before 37 weeks' gestation. The point estimates for the likelihood ratios (LRs) varied widely among the studies. LRs for an abnormal score (LR+) ranged from 1.0 (95% confidence interval (CI) 0.6-1.4) to 38.8 (95% CI 23.5-63.9) while that for a normal score (LR-) ranged from 0.1 (95% CI 0.02-0.6) to 1.2 (95% CI 0.9-1.6). In otherwise asymptomatic women, risk scoring in early pregnancy has a wide range of accuracy in predicting spontaneous preterm birth before 37 weeks' gestation. The evidence is of a relatively poor quality and lacks clinically important reference standards.

Female↗
PubMed2004

Variation in practice of laparoscopic uterosacral nerve ablation: a European survey.

To examine the variation in current indications and surgical techniques for performing laparoscopic uterosacral nerve ablation (LUNA) in Europe, all consultants on the databases of the UK Royal College of Obstetricians and Gynaecologists (1569) and the European Society of Gynaecological Endoscopy (301) were surveyed. The questionnaire was returned by 719 (38% of 1870) of the gynaecologists contacted and 173 (24%) performed LUNA. Indications for LUNA, which included chronic pelvic pain (68%), dysmenorrhoea (66%), dyspareunia (39%) and endometriosis (60%), were similar across the United Kingdom and the rest of Europe. The European group were more likely to perform LUNA (62% versus 21%), completely transect the uterosacral ligaments (56% versus 36%) and at a distance of more than 2 cm from its cervical insertion (50% versus 21%) than the UK group. There is variation in the surgical techniques of performing LUNA in Europe and the techniques vary according to operator experience.

Databases, Factual↗
PubMed2003

Accuracy of cervical transvaginal sonography in predicting preterm birth: a systematic review.

This review investigates the accuracy with which transvaginal cervical sonography predicts spontaneous preterm birth. Published studies were identified without language restrictions through nine different databases and manual searching of bibliographies of known primary and review articles. Studies were selected if they undertook antenatal transvaginal sonographic cervical assessment among a population of pregnant women with known gestational age of delivery. There were 46 primary articles, which included a total of 31,577 women, consisting of 33 studies in asymptomatic and 13 studies in symptomatic women. Data were extracted for the studies' characteristics and quality. Accuracy data were used to form 2 x 2 contingency tables for various cervical length measurements with birth before 32, 34 and 37 weeks' gestation as the reference standards. Data were stratified according to singleton or twin pregnancy, gestational age at testing, cervical length threshold, and the various reference standards, and were pooled to produce summary estimates of likelihood ratios (LRs). Our review showed that transvaginal cervical sonography identifies women who are at higher risk of spontaneous preterm birth, although there was a wide variation amongst studies with respect to gestational age at testing, definition of threshold of abnormality and definition of reference standard. The most commonly reported sub-group was testing of asymptomatic women at < 20 weeks' gestation using a threshold cervical length of 25 mm with spontaneous preterm birth before 34 weeks' gestation as the reference standard. The summary LR+ for this group was 6.29 (95% CI, 3.29-12.02), with corresponding LR- of 0.79 (95% CI, 0.65-0.95). Both cervical length measurement and funneling, whether alone or in combination, appear to be useful (depending on the threshold chosen to define the abnormality) in predicting spontaneous preterm birth in asymptomatic women. For symptomatic women there was a paucity of data, although the degree of funneling appeared to be predictive of spontaneous preterm birth.

Data Collection↗
PubMed2003

Multivariable analysis of tests for the diagnosis of intrauterine growth restriction.

OBJECTIVES: To describe how data from antenatal fetal ultrasound biometry, amniotic fluid index and umbilical artery Doppler can be appropriately combined using multivariable models and to investigate how the addition of these ultrasound parameters influences the ability to predict intrauterine growth restriction (IUGR). METHODS: This was a prospective cohort study involving 274 low-risk pregnancies undergoing serial ultrasound examination at predetermined intervals. Standard deviation (Z) scores of the last values for fetal abdominal area (FAA), growth velocity of the FAA, amniotic fluid index (AFI) and umbilical artery Doppler pulsatility index prior to delivery were calculated for 260 fetuses. Customized estimated fetal weight (cEFW) centiles were also calculated using the last EFW before delivery after adjustment for fetal gender, gestational age, birth order and maternal weight, height and ethnic origin. Following delivery the neonatal ponderal index was calculated and centile position obtained. A neonatal ponderal index <25(th) centile served as the main outcome measure for diagnosis of IUGR. Logistic regression analysis was used to delineate the predictive value of the three fetal growth tests FAA, FAA growth velocity and cEFW and the additional values of AFI and pulsatility index of the umbilical artery. RESULTS: The areas under the receiver-operating characteristics (ROC) curves (95% confidence interval) for FAA, FAA growth velocity and cEFW alone were 0.819 (0.748-0.891), 0.784 (0.699-0.869) and 0.74 (0.643-0.837), respectively, in the prediction of a neonatal ponderal index <25(th) centile. The addition of both the AFI and pulsatility index to FAA, FAA growth velocity and cEFW generated small increases in the areas, to 0.831 (0.758-0.904), 0.817 (0.735-0.899) and 0.766 (0.672-0.859), respectively. These improvements in diagnostic prediction were not statistically significant. CONCLUSIONS: The addition of AFI and umbilical artery pulsatility index to the fetal biometry parameters did not significantly increase the ROC areas in the study population. The approach applied in this study is useful in the context of hypothesis generation. Further studies using larger data sets and other predictors should be carried out using the analytical techniques outlined in this paper to determine the contribution of various antenatal tests in the prediction of IUGR.

Amniotic Fluid↗
PubMed2002

Risk factors associated with endometrial polyps in abnormal uterine bleeding.

OBJECTIVES: To evaluate the significance of various risk factors associated with endometrial polyps in women with abnormal uterine bleeding. METHODS: A prospective cohort study of 248 consecutive patients evaluated for abnormal uterine bleeding in a Rapid Access Ambulatory Diagnostic (RAAD) clinic was carried out from 1996 to 1997. Endometrial polyps were diagnosed using outpatient hysteroscopy and their histological nature was confirmed in all patients by performing inpatient polypectomy. Multivariate logistic regression modeling was used to evaluate the effects of age, parity, menopausal status, hormone replacement therapy and tamoxifen treatment on the occurrence of polyps. RESULTS: In an analysis adjusted for the effects of age, parity and menopausal status, tamoxifen treatment was associated with endometrial polyps (adjusted odds ratio 11.21, 95% confidence interval 2.70-46.46, P=0.0009) but hormone replacement therapy was not (adjusted odds ratio 1.48, 95% confidence interval 0.68-3.20, P=0.32). CONCLUSION: Our study confirmed that tamoxifen is associated with endometrial polyps. However, it rejects the hypothesis that hormone replacement therapy is a risk factor for endometrial polyps.

Antineoplastic Agents, Hormonal↗
PubMed2002

Utility of participatory rural appraisal for health needs assessment and planning.

BACKGROUND: While poverty and lack of life opportunities are root causes of a high burden of disease and infant and maternal mortality, inadequate health care contributes heavily. Often those who are left without care are those who need it most. Existing health services are managed without taking into account acceptance and need perspectives. This further reduces the effectiveness of and equity in health care. In order to guide the planning of reproductive health services by a national NGO, health needs were assessed in a district in Sindh using a combination of participatory rural appraisal (PRA) and qualitative and quantitative research methods. PRA is considered as a better framework to assess, analyse and develop programs with communities. OBJECTIVE: The objective of PRA was to initiate community involvement and to understand the needs of health care from a community perspective. METHODOLOGY: PRA was conducted with groups of men and women from three rural areas in a district of Sindh, Pakistan using a life cycle framework. The community members identified various stages of their life with the associated health issues. RESULTS: This research was empowering to community members as it facilitated community involvement. The respondents took charge of the process of identification of health needs at PRA sessions. PRA helped identify health problems considered prevalent and important by the community. More importantly, it helped potential service providers and the community to initiate community involvement in planning. CONCLUSION: PRA is not only an effective tool for assessment and analysis of health issues but also a vehicle to promote community involvement. Additionally, participatory methods contribute to understand the context of quantitative data generated for planning purposes.

Adolescent↗
PubMed2001

Effect of paper quality on the response rate to a postal survey: a randomised controlled trial. ISRCTN 32032031.

BACKGROUND: Response rates to surveys are declining and this threatens the validity and generalisability of their findings. We wanted to determine whether paper quality influences the response rate to postal surveys METHODS: A postal questionnaire was sent to all members of the British Society of Gynaecological Endoscopy (BSGE). Recipients were randomised to receiving the questionnaire printed on standard quality paper or high quality paper. RESULTS: The response rate for the recipients of high quality paper was 43/195 (22%) and 57/194 (29%) for standard quality paper (relative rate of response 0.75, 95% CI 0.33-1.05, p = 0.1 CONCLUSION: The use of high quality paper did not increase response rates to a questionnaire survey of gynaecologists affiliated to an endoscopic society.

Data Collection↗
PubMed2001

Comparison of search strategies and quality of medical information of the Internet: a study relating to ankle sprain.

OBJECTIVES: to evaluate the quality of web sites on ankle sprain diagnosis and treatment and to assess the impact of Internet search expertise on quality of retrieved information. METHOD: two internet search strategies were conducted - one developed by an experienced information officer (expert's search) and the other based on the search terms used by orthopaedic medical staff (doctors' search). RESULTS: the expert's search revealed 32 web sites, of which nine were relevant, whereas the doctors' search revealed 61 web sites of which 27 were relevant. Of the relevant web sites in the expert's search, one complied with all quality criteria, whereas none of the web sites in the doctors' search complied with all criteria (11 vs. 0%, P=0.25). The web sites identified by expert's search had higher credibility (median scores 70 vs. 44, P=0.01) and accuracy of content (median scores 50 vs. 35, P=0.24). CONCLUSION: the quality of medical information on the internet is generally poor and information experts can capture higher quality web sites compared with doctors.

Ankle Injuries↗
PubMed2001

Interval between fetal measurements in predicting growth restriction.

OBJECTIVE: To determine the influence of the interval between fetal measurements on performance of fetal growth velocity for predicting infants with anthropometric features of fetal growth restriction (FGR). METHODS: Two hundred seventy-four low-risk women had serial fetal biometry at scheduled intervals. Growth velocity of the fetal abdominal area for each was calculated with 2-, 4-, and 6-week scan intervals in which the second measurement was the last scan before delivery. Fetal abdominal area velocity over a 4-week interval in the early third trimester also was included. Fetal growth restriction was defined as skinfold thickness under the tenth percentile, ponderal index under the 25th percentile, midarm circumference-to-occipitofrontal circumference ratio of under -1 standard deviation (SD). Test performance was expressed as likelihood ratios with 95% confidence intervals (CI). RESULTS: Fetal abdominal area velocity calculated over a 4-week interval predicted FGR with a likelihood ratio of 10.4 (95% CI 3.9, 26) for skinfold thickness; 9.5 (95% CI 4.6, 19) for ponderal index; and 4.7 (2.3, 8.4) for midarm circumference-to-occipitofrontal circumference ratio. Intermeasurement intervals of 6 weeks had a likelihood ratio of 8.5 (95% CI 4, 17) for skinfold thickness; 7.5 (95% CI 3.4, 16.1) for ponderal index; and 14 (6.7, 28) for midarm circumference-to-occipitofrontal circumference ratio. The likelihood ratios for the 2-week interval and the early third trimester 4-week interval were all less than 5. CONCLUSION: Four- and 6-week measurement intervals were useful for predicting infants with FGR and were superior to a 2-week interval. Fetal growth velocity is influenced by proximity of the last fetal measurement to date of delivery, which adversely affects clinical use of growth velocity for predicting FGR.

Adult↗
PubMed2001

Noninvasive techniques to detect fetal anemia due to red blood cell alloimmunization: a systematic review.

OBJECTIVE: To estimate, in maternal red blood cell alloimmunization, the diagnostic value of fetal ultrasonography and Doppler blood flow velocity in the evaluation and prediction of fetal anemia. METHODS: Literature from 1970 to 2000 was identified using general bibliographic databases (MEDLINE and EMBASE), the Cochrane Library and relevant specialist register of the Cochrane Collaboration, and by checking reference lists of known primary and review articles. Studies were selected if the accuracy of the fetal ultrasound parameters or Doppler studies of blood flow in the fetal vessels was estimated compared with a reference standard (fetal hemoglobin). The diagnostic tests evaluated were ultrasound measurement of the fetal spleen perimeter and Doppler studies of blood velocity estimates in the umbilical vein, ductus venosus, middle cerebral artery, thoracic aorta, and umbilical vessel combined with the thoracic aorta. Study selection, quality assessment, and data abstraction were performed independently and in duplicate. Data from the selected studies were abstracted as 2 x 2 tables comparing the diagnostic test result with the reference standard. Diagnostic accuracy was expressed as likelihood ratios. RESULTS: The review included eight primary studies with 362 pregnancies affected by red cell alloimmunization. Prospective patient recruitment and complete population details were reported in half of the selected studies (four of eight). Only one study reported masking the diagnostic test results to clinicians. The diagnostic test performance varied widely according to the type of the test evaluated and the cutoff level used to define fetal anemia, which varied from study to study. The diagnostic test study of highest methodological quality reported a positive likelihood ratio of 8.45 (95% confidence interval 4.69, 15.56) and negative likelihood ratio of 0.02 (95% confidence interval 0.001, 0.25) for maximum middle cerebral artery Doppler velocity. CONCLUSION: The literature reporting noninvasive techniques to predict fetal anemia is methodologically poor and a standard approach to the evaluation of these techniques is lacking. A recommendation for practice cannot be generated without further rigorous research.

Blood Flow Velocity↗
PubMed2001

Aspirin for the prevention of preeclampsia in women with abnormal uterine artery Doppler: a meta-analysis.

OBJECTIVE: To determine the effectiveness of aspirin to prevent preeclampsia in women identified as high risk for preeclampsia by an abnormal second-trimester uterine artery Doppler examination. DATA SOURCES: Searches were conducted in MEDLINE, Embase, the Cochrane Controlled Trials Register, and Science Citation Index for randomized trials published from 1966 to 2000, using the following medical subject headings and key words: "aspirin," "antiplatelet*," "salicyl*," "acetylsalicyl*," "platelet aggregation inhibitors," "ultrasonography," "ultraso*," and "Doppler." STUDY SELECTION: We included all randomized trials that evaluated the effectiveness of aspirin compared with placebo or no treatment in women with an abnormal uterine artery Doppler and that reported clinically relevant perinatal and maternal outcomes. Study selection, quality assessment, and data extraction were performed in duplicate. TABULATION, INTEGRATION, AND RESULTS: There were five relevant trials. Pooling of results from these trials showed a significant benefit of aspirin in reducing preeclampsia (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.32, 0.95). The baseline risk of preeclampsia in women with abnormal uterine artery Doppler was 16%, and the number of women needed to be treated with aspirin to prevent one case of preeclampsia was 16 (95% CI 8, 316). Women on aspirin had babies who were on average 82 g heavier than controls, but this result did not reach statistical significance (weighted mean difference 81.5, 95% CI 40.27, 203.27). CONCLUSION: Uterine artery Doppler assessment identifies high-risk women in whom aspirin therapy results in a significant reduction in preeclampsia.

Aspirin↗