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Ian Roberts

Publications and source records attributed to Ian Roberts.

At least 55 records · Page 3Linked to original sources
PubMed2003

Genomic imbalances in CML blast crisis: 8q24.12-q24.13 segment identified as a common region of over-representation.

The acute phase of chronic myeloid leukemia (CML) is accompanied by secondary chromosomal changes. The additional changes have a non-random pattern; however, highly abnormal (marker) chromosomes are reported in some 20% of abnormal karyotypes. These marker chromosomes have proved to be beyond the resolution of conventional G-banding analysis. We used molecular cytogenetic techniques to determine the structure of complex chromosome markers in 10 CML-derived cell lines after our investigations of CML patients in blast crisis. Multicolor fluorescence in situ hybridization identified a multitude of structural chromosome aberrations. In addition, genomic gains identified by comparative genomic hybridization (CGH) were mapped to highly complex marker chromosomes in more than one cell line. The most common genomic loss detected by CGH affected chromosome 9, whereas the most common genomic gains affected, in order of frequency, the sequences of 8q, 6, and 13q. The smallest discrete amplification on 8q was identified in cell line MEG-01. This amplicon contains sequences represented by the marker D8S263/RMC08P029 but did not contain the proximal MYC gene or a more distal marker, D8S256/RMC08P025. We determined the size of the amplicon to be less than the chromosome segment 8q24.12-q24.13. The use of region- and locus-specific probes to analyze the organization of highly complex marker structures aided the identification of preferentially amplified genomic regions. The resultant amplifications could harbor gene(s) driving disease progression.

Allelic Imbalance↗
PubMed2003

Fluid resuscitation strategies: a systematic review of animal trials.

OBJECTIVES: Our objective was to systematically review randomized, controlled trials of fluid resuscitation in animal models of uncontrolled hemorrhage and to explore potential sources of heterogeneity. METHODS: We conducted an electronic bibliographic search of published research, reviewed reference lists of included trials, and contacted authors about unpublished studies. We included all unconfounded, randomized, controlled trials of fluid resuscitation (timing, volume, or resuscitation targets) in animal models of uncontrolled hemorrhage. The outcome measure was mortality at the end of the scheduled follow-up period of the trial. Two reviewers independently applied the selection criteria to the trial reports. A third reviewer resolved disagreements. RESULTS: Forty-four trials compared fluid versus no fluid resuscitation. There was marked heterogeneity in the effect of fluid resuscitation on the risk of death, much of which was explained by the hemorrhage model used. In aortic injury models, the adjusted relative risk of death with fluid resuscitation was 0.48 (95% confidence interval [CI], 0.33-0.71). In organ incision models, the adjusted relative risk of death was 0.76 (95% CI, 0.49-1.18). In tail resection models, the adjusted relative risk of death was 0.69 (95% CI, 0.38-1.25) if 50% or more was removed and 1.86 (95% CI, 1.13-3.07) if less than 50% was removed. In other vascular injury models, the adjusted relative risk of death with fluid resuscitation was 1.70 (95% CI, 1.01-2.85), respectively. Nine trials compared hypotensive versus normotensive resuscitation. The relative risk of death with hypotensive resuscitation was 0.37 (95% CI, 0.27-0.50). CONCLUSION: Fluid resuscitation appears to reduce the risk of death in animal models of severe hemorrhage but increases the risk of death in those with less severe hemorrhage. Excessive fluid resuscitation could therefore be harmful in some situations. Hypotensive resuscitation reduced the risk of death in all the trials investigating it. An evaluation of the potential impact of hypotensive resuscitation in humans could now be warranted.

Animals↗
PubMed2002

Incidence of fires and related injuries after giving out free smoke alarms: cluster randomised controlled trial.

OBJECTIVE: To measure the effect of giving out free smoke alarms on rates of fires and rates of fire related injury in a deprived multiethnic urban population. DESIGN: Cluster randomised controlled trial. SETTING: Forty electoral wards in two boroughs of inner London, United Kingdom. PARTICIPANTS: Primarily households including elderly people or children and households that are in housing rented from the borough council. INTERVENTION: 20 050 smoke alarms, fittings, and educational brochures distributed free and installed on request. MAIN OUTCOME MEASURES: Rates of fires and related injuries during two years after the distribution; alarm ownership, installation, and function. RESULTS: Giving out free smoke alarms did not reduce injuries related to fire (rate ratio 1.3; 95% confidence interval 0.9 to 1.9), admissions to hospital and deaths (1.3; 0.7 to 2.3), or fires attended by the fire brigade (1.1; 0.96 to 1.3). Similar proportions of intervention and control households had installed alarms (36/119 (30%) v 35/109 (32%); odds ratio 0.9; 95% confidence interval 0.5 to 1.7) and working alarms (19/118 (16%) v 18/108 (17%); 0.9; 0.4 to 1.8). CONCLUSIONS: Giving out free smoke alarms in a deprived, multiethnic, urban community did not reduce injuries related to fire, mostly because few alarms had been installed or were maintained.

Burns↗
PubMed2002

Prevalence of working smoke alarms in local authority inner city housing: randomised controlled trial.

OBJECTIVES: To identify which type of smoke alarm is most likely to remain working in local authority inner city housing, and to identify an alarm tolerated in households with smokers. DESIGN: Randomised controlled trial. SETTING: Two local authority housing estates in inner London. PARTICIPANTS: 2145 households. INTERVENTION: Installation of one of five types of smoke alarm (ionisation sensor with a zinc battery; ionisation sensor with a zinc battery and pause button; ionisation sensor with a lithium battery and pause button; optical sensor with a lithium battery; or optical sensor with a zinc battery). MAIN OUTCOME MEASURE: Percentage of homes with any working alarm and percentage in which the alarm installed for this study was working after 15 months. RESULTS: 54.4% (1166/2145) of all households and 45.9% (465/1012) of households occupied by smokers had a working smoke alarm. Ionisation sensor, lithium battery, and there being a smoker in the household were independently associated with whether an alarm was working (adjusted odds ratios 2.24 (95% confidence interval 1.75 to 2.87), 2.20 (1.77 to 2.75), and 0.62 (0.52 to 0.74)). The most common reasons for non-function were missing battery (19%), missing alarm (17%), and battery disconnected (4%). CONCLUSIONS: Nearly half of the alarms installed were not working when tested 15 months later. Type of alarm and power source are important determinants of whether a household had a working alarm.

Electric Power Supplies↗
PubMed2002

Identification of randomized controlled trials in systematic reviews: accuracy and reliability of screening records.

A study was conducted to estimate the accuracy and reliability of reviewers when screening records for relevant trials for a systematic review. A sensitive search of ten electronic bibliographic databases yielded 22 571 records of potentially relevant trials. Records were allocated to four reviewers such that two reviewers examined each record and so that identification of trials by each reviewer could be compared with those identified by each of the other reviewers. Agreement between reviewers was assessed using Cohen's kappa statistic. Ascertainment intersection methods were used to estimate the likely number of trials missed by reviewers. Full copies of reports were obtained and assessed independently by two researchers for eligibility for the review. Eligible reports formed the 'gold standard' against which an assessment was made about the accuracy of screening by reviewers. After screening, 301 of 22 571 records were identified by at least one reviewer as potentially relevant. Agreement was 'almost perfect' (kappa>0.8) within two pairs, 'substantial' (kappa>0.6) within three pairs and 'moderate' (kappa>0.4) within one pair. Of the 301 records selected, 273 complete reports were available. When pairs of reviewers agreed on the potential relevance of records, 81 per cent were eligible (range 69 to 91 per cent). If reviewers disagreed, 22 per cent were eligible (range 12 to 45 per cent). Single reviewers missed on average 8 per cent of eligible reports (range 0 to 24 per cent), whereas pairs of reviewers did not miss any (range 0 to 1 per cent). The use of two reviewers to screen records increased the number of randomized trials identified by an average of 9 per cent (range 0 to 32 per cent). Reviewers can reliably identify potentially relevant records when screening thousands of records for eligibility. Two reviewers should screen records for eligibility, whenever possible, in order to maximize ascertainment of relevant trials.

Databases, Bibliographic↗
PubMed2002

Increasing response rates to postal questionnaires: systematic review.

OBJECTIVE: To identify methods to increase response to postal questionnaires. DESIGN: Systematic review of randomised controlled trials of any method to influence response to postal questionnaires. STUDIES REVIEWED: 292 randomised controlled trials including 258 315 participants INTERVENTION REVIEWED: 75 strategies for influencing response to postal questionnaires. MAIN OUTCOME MEASURE: The proportion of completed or partially completed questionnaires returned. RESULTS: The odds of response were more than doubled when a monetary incentive was used (odds ratio 2.02; 95% confidence interval 1.79 to 2.27) and almost doubled when incentives were not conditional on response (1.71; 1.29 to 2.26). Response was more likely when short questionnaires were used (1.86; 1.55 to 2.24). Personalised questionnaires and letters increased response (1.16; 1.06 to 1.28), as did the use of coloured ink (1.39; 1.16 to 1.67). The odds of response were more than doubled when the questionnaires were sent by recorded delivery (2.21; 1.51 to 3.25) and increased when stamped return envelopes were used (1.26; 1.13 to 1.41) and questionnaires were sent by first class post (1.12; 1.02 to 1.23). Contacting participants before sending questionnaires increased response (1.54; 1.24 to 1.92), as did follow up contact (1.44; 1.22 to 1.70) and providing non-respondents with a second copy of the questionnaire (1.41; 1.02 to 1.94). Questionnaires designed to be of more interest to participants were more likely to be returned (2.44; 1.99 to 3.01), but questionnaires containing questions of a sensitive nature were less likely to be returned (0.92; 0.87 to 0.98). Questionnaires originating from universities were more likely to be returned than were questionnaires from other sources, such as commercial organisations (1.31; 1.11 to 1.54). CONCLUSIONS: Health researchers using postal questionnaires can improve the quality of their research by using the strategies shown to be effective in this systematic review.

Data Collection↗
PubMed2002

War on the roads.

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Accidents, Traffic↗
PubMed2002

Safety education of pedestrians for injury prevention: a systematic review of randomised controlled trials.

OBJECTIVES: To quantify the effectiveness of safety education of pedestrians. DESIGN: Systematic review of randomised controlled trials of safety education programmes for pedestrians of all ages. MAIN OUTCOME MEASURES: Effect of safety education on pedestrians' injuries, behaviour, attitude, and knowledge and on pedestrian-motor vehicle collisions. Quality of trials: methods of randomisation; and numbers lost to follow up. RESULTS: We identified 15 randomised controlled trials of safety education programmes for pedestrians. Fourteen trials targeted children, and one targeted institutionalised adults. None assessed the effect of safety education on the occurrence of pedestrian injury, but six trials assessed its effect on behaviour. The effect of pedestrian education on behaviour varied considerably across studies and outcomes. CONCLUSIONS: Pedestrian safety education can change observed road crossing behaviour, but whether this reduces the risk of pedestrian injury in road traffic crashes is unknown. There is a lack of good evidence of effectiveness of safety education for adult pedestrians, specially elderly people. None of the trials was conducted in low or middle income countries.

Accidents, Traffic↗
PubMed2002

Prevention of deaths and injuries caused by house fires: survey of local authority smoke alarm policies.

BACKGROUND: Despite an increased risk of fire in disadvantaged households, smoke alarm ownership is considerably lower than in the general population. The government currently recommends that local authorities install battery-operated smoke alarms in all public sector properties regardless of tenure. However, the extent to which local authorities comply is currently not known. We conducted a survey of local authorities to establish the extent of their smoke alarm provision to public sector households. METHODS: A telephone survey of all 405 local authorities within England and Wales was carried out. RESULTS: We obtained responses from 390 (97 per cent) local authorities, 266 of which had responsibility for housing. Over half of all public-sector households are offered smoke alarms by the local authorities. The majority of local authorities offer ionization and/or optical sensor alarm types (78 per cent), with many local authorities providing battery-operated alarms alone (17 per cent) or in combination with hardwired alarms (31 per cent). CONCLUSIONS: Many local authorities offer smoke alarm provision to their public-sector households. Whether this represents an effective and cost-effective use of resources requires further investigation.

Data Collection↗
PubMed2002

Crash.

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Adrenal Cortex Hormones↗
PubMed2002

Egg on their faces. The story of human albumin solution.

In 1998, the Cochrane Injuries Group published the results of a systematic review of human albumin administration in critically ill patients. The results showed that the risk of death in patients receiving albumin was 14%, and the risk of death in patients not receiving albumin was 8%, suggesting that for every 17 critically ill patients treated with albumin there is one extra death. The results were widely reported in the television and print media throughout the world and stimulated an immediate response from the drug regulatory agencies, the plasma products industry, and the medical profession. Despite vigorous attempts by the plasma products industry to limit the effect of the systematic review on albumin sales, the use of albumin declined steeply, showing that evidence from systematic reviews can have an important effect on clinical care.

Albumins↗