Observation of B_{s}^{0}→D[over ¯]^{0}K_{S}^{0} and Evidence for B_{s}^{0}→D[over ¯]^{*}^{0}K_{S}^{0} Decays

The first observation of the B_{s}^{0}→D[over ¯]^{0}K_{S}^{0} decay mode and evidence for the B_{s}^{0}→D[over ¯]^{*0}K_{S}^{0} decay mode are reported. The data sample corresponds to an integrated luminosity of 3.0  fb^{-1} collected in pp collisions by LHCb at center-of-mass energies of 7 and 8 TeV. The branching fractions are measured to be B(B_{s}^{0}→D[over ¯]^{0}K[over ¯]^{0})=[4.3±0.5(stat)±0.3(syst)±0.3(frag)±0.6(norm)]×10^{-4},B(B_{s}^{0}→D[over ¯]^{*0}K[over ¯]^{0})=[2.8±1.0(stat)±0.3(syst)±0.2(frag)±0.4(norm)]×10^{-4},where the uncertainties are due to contributions coming from statistical precision, systematic effects, and the precision of two external inputs, the ratio f_{s}/f_{d} and the branching fraction of B^{0}→D[over ¯]^{0}K_{S}^{0}, which is used as a calibration channel.

Evidence for the Strangeness-Changing Weak Decay Ξ_{b}^{-}→Λ_{b}^{0}π^{-}

Using a pp collision data sample corresponding to an integrated luminosity of 3.0  fb^{-1}, collected by the LHCb detector, we present the first search for the strangeness-changing weak decay Ξ_{b}^{-}→Λ_{b}^{0}π^{-}. No b hadron decay of this type has been seen before. A signal for this decay, corresponding to a significance of 3.2 standard deviations, is reported. The relative rate is measured to be f_{Ξ_{b}^{-}}/f_{Λ_{b}^{0}}B(Ξ_{b}^{-}→Λ_{b}^{0}π^{-})=(5.7±1.8_{-0.9}^{+0.8})×10^{-4},where f_{Ξ_{b}^{-}} and f_{Λ_{b}^{0}} are the b→Ξ_{b}^{-} and b→Λ_{b}^{0} fragmentation fractions, and B(Ξ_{b}^{-}→Λ_{b}^{0}π^{-}) is the branching fraction. Assuming f_{Ξ_{b}^{-}}/f_{Λ_{b}^{0}} is bounded between 0.1 and 0.3, the branching fraction B(Ξ_{b}^{-}→Λ_{b}^{0}π^{-}) would lie in the range from (0.57±0.21)% to (0.19±0.07)%.

Search for Hidden-Sector Bosons in B(0)→K(*0)μ(+)μ(-) Decays

A search is presented for hidden-sector bosons, χ, produced in the decay B(0)→K*(892)(0)χ, with K*(892)(0)→K(+)π(-) and χ→μ(+)μ(-). The search is performed using pp-collision data corresponding to 3.0  fb(-1) collected with the LHCb detector. No significant signal is observed in the accessible mass range 214≤m(χ)≤4350  MeV, and upper limits are placed on the branching fraction product B(B(0)→K*(892)(0)χ)×B(χ→μ(+)μ(-)) as a function of the mass and lifetime of the χ boson. These limits are of the order of 10(-9) for χ lifetimes less than 100 ps over most of the m(χ) range, and place the most stringent constraints to date on many theories that predict the existence of additional low-mass bosons.

First observation of top quark production in the forward region

Top quark production in the forward region in proton-proton collisions is observed for the first time. The W+b final state with W→μν is reconstructed using muons with a transverse momentum, p_{T}, larger than 25 GeV in the pseudorapidity range 2.0<η<4.5. The b jets are required to have 50<p_{T}<100  GeV and 2.2<η<4.2, while the transverse component of the sum of the muon and b-jet momenta must satisfy p_{T}>20  GeV. The results are based on data corresponding to integrated luminosities of 1.0 and 2.0  fb^{-1} collected at center-of-mass energies of 7 and 8 TeV by LHCb. The inclusive top quark production cross sections in the fiducial region are σ(top)[7  TeV]=239±53(stat)±33(syst)±24(theory)  fb,σ(top)[8  TeV]=289±43(stat)±40(syst)±29(theory)  fb.These results, along with the observed differential yields and charge asymmetries, are in agreement with next-to-leading order standard model predictions.

Measurement of the ratio of branching fractions B(B[over ¯]^{0}→D^{*+}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]^{0}→D^{*+}μ^{-}ν[over ¯]_{μ})

The branching fraction ratio R(D^{*})≡B(B[over ¯]^{0}→D^{*+}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]^{0}→D^{*+}μ^{-}ν[over ¯]_{μ}) is measured using a sample of proton-proton collision data corresponding to 3.0  fb^{-1} of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ}. The semitauonic decay is sensitive to contributions from non-standard-model particles that preferentially couple to the third generation of fermions, in particular, Higgs-like charged scalars. A multidimensional fit to kinematic distributions of the candidate B[over ¯]^{0} decays gives R(D^{*})=0.336±0.027(stat)±0.030(syst). This result, which is the first measurement of this quantity at a hadron collider, is 2.1 standard deviations larger than the value expected from lepton universality in the standard model.

Observation of J/ψp Resonances Consistent with Pentaquark States in Λ_{b}^{0}→J/ψK^{-}p Decays

Observations of exotic structures in the J/ψp channel, which we refer to as charmonium-pentaquark states, in Λ_{b}^{0}→J/ψK^{-}p decays are presented. The data sample corresponds to an integrated luminosity of 3 fb^{-1} acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude analysis of the three-body final state reproduces the two-body mass and angular distributions. To obtain a satisfactory fit of the structures seen in the J/ψp mass spectrum, it is necessary to include two Breit-Wigner amplitudes that each describe a resonant state. The significance of each of these resonances is more than 9 standard deviations. One has a mass of 4380±8±29 MeV and a width of 205±18±86 MeV, while the second is narrower, with a mass of 4449.8±1.7±2.5 MeV and a width of 39±5±19 MeV. The preferred J^{P} assignments are of opposite parity, with one state having spin 3/2 and the other 5/2.

Analysis of Mll1 deficiency identifies neurogenic transcriptional modules and Brn4 as a factor for direct astrocyte-to-neuron reprogramming

BACKGROUND

Mixed lineage leukemia-1 (Mll1) epigenetically regulates gene expression patterns that specify cellular identity in both embryonic development and adult stem cell populations. In the adult mouse brain, multipotent neural stem cells (NSCs) in the subventricular zone generate new neurons throughout life, and Mll1 is required for this postnatal neurogenesis but not for glial cell differentiation. Analysis of Mll1-dependent transcription may identify neurogenic genes useful for the direct reprogramming of astrocytes into neurons.

OBJECTIVE

To identify Mll1-dependent transcriptional modules and to determine whether genes in the neurogenic modules can be used to directly reprogram astrocytes into neurons.

METHODS

We performed gene coexpression module analysis on microarray data from differentiating wild-type and Mll1-deleted subventricular zone NSCs. Key developmental regulators belonging to the neurogenic modules were overexpressed in Mll1-deleted cells and cultured cortical astrocytes, and cell phenotypes were analyzed by immunocytochemistry and electrophysiology.

RESULTS

Transcriptional modules that correspond to neurogenesis were identified in wild-type NSCs. Modules related to astrocytes and oligodendrocytes were enriched in Mll1-deleted NSCs, consistent with their gliogenic potential. Overexpression of genes selected from the neurogenic modules enhanced the production of neurons from Mll1-deleted cells, and overexpression of Brn4 (Pou3f4) in nonneurogenic cortical astroglia induced their transdifferentiation into electrophysiologically active neurons.

CONCLUSION

Our results demonstrate that Mll1 is required for the expression of neurogenic but not gliogenic transcriptional modules in a multipotent NSC population and further indicate that specific Mll1-dependent genes may be useful for direct reprogramming strategies.

Observation of the B(s)(0)→η'η' Decay

The first observation of the B(s)(0)→η'η' decay is reported. The study is based on a sample of proton-proton collisions corresponding to 3.0  fb(-1) of integrated luminosity collected with the LHCb detector. The significance of the signal is 6.4 standard deviations. The branching fraction is measured to be [3.31±0.64(stat)±0.28(syst)±0.12(norm)]×10(-5), where the third uncertainty comes from the B(±)→η'K(±) branching fraction that is used as a normalization. In addition, the charge asymmetries of B(±)→η'K(±) and B(±)→ϕK(±), which are control channels, are measured to be (-0.2±1.3)% and (+1.7±1.3)%, respectively. All results are consistent with theoretical expectations.

Measurement of CP Violation in B0→J/ψK{S}^{0} Decays

Measurements are presented of the CP violation observables S and C in the decays of B(0) and Bover ¯]0 mesons to the J/ψK(S)(0) final state. The data sample corresponds to an integrated luminosity of 3.0  fb(-1) collected with the LHCb experiment in proton-proton collisions at center-of-mass energies of 7 and 8 TeV, and contains a total of 41 560 selected B^{0} and B[over ¯]^{0} decays. The analysis of the time evolution of these decays yields S=0.731±0.035(stat)±0.020(syst) and C=-0.038±0.032(stat)±0.005(syst). In the standard model, S equals sin(2β) to a good level of precision. The values are consistent with the current world averages and with the standard model expectations.

OTX2 Transcription Factor Controls Regional Patterning within the Medial Ganglionic Eminence and Regional Identity of the Septum

The Otx2 homeodomain transcription factor is essential for gastrulation and early neural development. We generated Otx2 conditional knockout (cKO) mice to investigate its roles in telencephalon development after neurulation (approximately embryonic day 9.0). We conducted transcriptional profiling and in situ hybridization to identify genes de-regulated in Otx2 cKO ventral forebrain. In parallel, we used chromatin immunoprecipitation sequencing to identify enhancer elements, the OTX2 binding motif, and de-regulated genes that are likely direct targets of OTX2 transcriptional regulation. We found that Otx2 was essential in septum specification, regulation of Fgf signaling in the rostral telencephalon, and medial ganglionic eminence (MGE) patterning, neurogenesis, and oligodendrogenesis. Within the MGE, Otx2 was required for ventral, but not dorsal, identity, thus controlling the production of specific MGE derivatives.

Measurement of Bc+ Production in Proton-Proton Collisions at √[s]=8 TeV

Production of Bc+ mesons in proton-proton collisions at a center-of-mass energy of 8 TeV is studied with data corresponding to an integrated luminosity of 2.0  fb-1 recorded by the LHCb experiment. The ratio of production cross sections times branching fractions between the Bc+→J/ψπ+ and B+→J/ψK+ decays is measured as a function of transverse momentum and rapidity in the regions 0<pT<20  GeV/c and 2.0<y<4.5. The ratio in this kinematic range is measured to be (0.683±0.018±0.009)%, where the first uncertainty is statistical and the second systematic.

Observation of two new Ξ(b)(-) baryon resonances

Two structures are observed close to the kinematic threshold in the Ξ(b)(0)π(-) mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0  fb(-1), recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content bds are expected in this mass region: the spin-parity J(P)=(1/2)(+) and J(P)=(3/2)(+) states, denoted Ξ(b)('-) and Ξ(b)(*-). Interpreting the structures as these resonances, we measure the mass differences and the width of the heavier state to be m(Ξ(b)('-))-m(Ξ(b)(0))-m(π(-))=3.653±0.018±0.006  MeV/c(2), m(Ξ(b)(*-))-m(Ξ(b)(0))-m(π(-))=23.96±0.12±0.06  MeV/c(2), Γ(Ξ(b)(*-))=1.65±0.31±0.10  MeV, where the first and second uncertainties are statistical and systematic, respectively. The width of the lighter state is consistent with zero, and we place an upper limit of Γ(Ξ(b)('-))<0.08  MeV at 95% confidence level. Relative production rates of these states are also reported.

Precision measurement of CP violation in B(S)(0)→J/ΨK+K- decays

The time-dependent CP asymmetry in B(s)(0)→J/ψK+K- decays is measured using pp collision data, corresponding to an integrated luminosity of 3.0  fb-1, collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV. In a sample of 96,000 B(s)(0)→J/ψK+K- decays, the CP-violating phase ϕs is measured, as well as the decay widths ΓL and ΓH of the light and heavy mass eigenstates of the B(s)(0)-B[over ¯]s0 system. The values obtained are ϕs=-0.058±0.049±0.006  rad, Γs≡(ΓL+ΓH)/2=0.6603±0.0027±0.0015  ps-1, and ΔΓs≡ΓL-ΓH=0.0805±0.0091±0.0032  ps-1, where the first uncertainty is statistical and the second, systematic. These are the most precise single measurements of those quantities to date. A combined analysis with Bs0→J/ψπ+π- decays gives ϕs=-0.010±0.039  rad. All measurements are in agreement with the standard model predictions. For the first time, the phase ϕs is measured independently for each polarization state of the K+K- system and shows no evidence for polarization dependence.

Measurement of the semileptonic CP asymmetry in B0-B[over ¯]0 mixing

The semileptonic CP asymmetry in B0-B[over ¯]0 mixing, a(sl)(d), is measured in proton-proton collision data, corresponding to an integrated luminosity of 3.0  fb-1, recorded by the LHCb experiment. Semileptonic B0 decays are reconstructed in the inclusive final states D-μ+ and D*-μ+, where the D- meson decays into the K+π-π- final state and the D*- meson into the D[over ¯]0(→K+π-)π- final state. The asymmetry between the numbers of D(*)-μ+ and D(*)+μ- decays is measured as a function of the decay time of the B0 mesons. The CP asymmetry is measured to be a(sl)(d)=(-0.02±0.19±0.30)%, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of a(sl)(d) to date and is consistent with the prediction from the standard model.

Precision measurement of the mass and lifetime of the Ξb⁻ baryon

We report on measurements of the mass and lifetime of the Ξ(b)⁻ baryon using about 1800 Ξ(b)⁻ decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0  fb⁻¹ collected by the LHCb experiment. The decays are reconstructed in the Ξ(b)⁻→Ξ(c)⁰π⁻, Ξ(c)⁰→pK⁻K⁻π⁺ channel and the mass and lifetime are measured using the Λ(b)⁰→Λ(c)⁺π⁻ mode as a reference. We measure M(Ξ(b)⁻)-M(Λ(b)⁰)=178.36±0.46±0.16  MeV/c², (τ(Ξ(b)⁻)/τ(Λ(b)⁰)=1.089±0.026±0.011, where the uncertainties are statistical and systematic, respectively. These results lead to a factor of 2 better precision on the Ξ(b)⁻ mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations.

Measurement of the CP-violating phase ϕs in Bs(0)→Ds(+)Ds(-) decays

We present a measurement of the CP-violating weak mixing phase ϕs using the decay Bs(0)→Ds(+)Ds(-) in a data sample corresponding to 3.0 fb(-1) of integrated luminosity collected with the LHCb detector in pp collisions at center-of-mass energies of 7 and 8 TeV. An analysis of the time evolution of the system, which does not use the constraint |λ|=1 to allow for the presence of CP violation in decay, yields ϕs=0.02±0.17(stat)±0.02(syst)  rad, |λ|=0.91(-0.15)(+0.18)(stat)±0.02(syst). This result is consistent with the standard model expectation.

Effects of short-term sitagliptin treatment on immune parameters in healthy individuals, a randomized placebo-controlled study

Sitagliptin, a dipeptidyl-peptidase 4 (DPP-4) inhibitor, improves blood glucose control in patients with type 2 diabetes by blocking cleavage of glucagon-like peptide 1 (GLP-1). In type 2 diabetes patients sitagliptin use is associated with an increase in minor infections, and in new-onset type 1 diabetes patients the ability of sitagliptin to dampen autoimmunity is currently being tested. DPP-4, also known as CD26, is expressed on leucocytes and can inactivate many chemokines important for leucocyte migration, as well as act as a co-stimulatory molecule on T cells. Therefore, this study was conducted to test whether sitagliptin is immunomodulatory. In this randomized, placebo-controlled trial, healthy volunteers were given sitagliptin or placebo daily for 28 days, and blood was drawn for immune assays. No significant differences were observed in the percentage of leucocyte subsets within peripheral blood mononuclear cells (PBMCs), plasma chemokine/cytokine levels or cytokines released by stimulation of PBMCs with either lipopolysaccharide (LPS) or anti-CD3. Individuals taking sitagliptin displayed increases in the percentage of cells expressing higher levels of CD26 at early time-points compared to placebo controls, but these differences resolved by day 28 of treatment. Therefore, in healthy volunteers, treatment with sitagliptin daily for 28 days does not overtly alter systemic immune function.

Time-frequency analysis of the ECG in the diagnosis of vasovagal syndrome in older people

The Smoothed Pseudo Wigner-Ville Distribution (SPWVD) is used for the time-frequency analysis of variations in RR interval. A novel technique to determine the smoothing window lengths is implemented, and a new heart rate variability (HRV) metric is developed, instantaneous center frequency variability (ICFV), which uses the time-frequency map generated by the SPWVD. The technique is then applied to 50 patients with unexplained falls and age > 60, undergoing head-upright tilt table testing (HUT). Eighteen of the patients were diagnosed with vasovagal syndrome. Attempts at syncope prediction using the new metric is an improvement on traditional techniques: an ICFV less than 0.07 Hz from 90 s to 180 s after tilt is predictive of a negative test (negative predictive value: 0.77). The comorbidity and autonomic degeneration present in elderly patients are thought to be responsible for lowering the negative predictive value.

A randomised controlled trial of the effect of continuous electronic physiological monitoring on the adverse event rate in high risk medical and surgical patients

We conducted a randomised controlled trial of mandated five-channel physiological monitoring vs standard care, in acute medical and surgical wards in a single UK teaching hospital. In all, 402 high-risk medical and surgical patients were studied. The primary outcome was the proportion of patients experiencing one or more major adverse events, including urgent staff calls, changes to higher care levels, cardiac arrests or death, in 96 h following randomisation. Secondary outcomes were the proportion of patients requiring acute treatment changes, and the 30-day and hospital mortality. In the 96 h following randomisation, 113 (56%) patients in the monitored arm and 116 (58%) in the control arm (OR 0.94, 95% CI 0.63-1.40, p = 0.76) had a major event. An acute change in treatment was necessary in 107 (53%) monitored patients and 101 (50%) control patients (OR 0.55, 95% CI 0.87-1.29). Thirty-four (17%) monitored patients and 35 (17%) control patients died within 30 days. Thirteen patients in the control group received full five-channel monitoring at the request of the ward staff. We conclude that mandated electronic vital signs monitoring in high risk medical and surgical patients has no effect on adverse events or mortality.

Deep wound infection after proximal femoral fracture: consequences and costs

The purpose of this study was to assess the impact of deep wound infection after surgery for proximal femoral fracture (PFF) on the patient in terms of mortality and social consequences, and on the National Health Service in terms of financial burden. Sixty-one cases of PFF over a six-year period were complicated with deep surgical wound infection. These cases were compared with a matched control group of 122 patients without infection. Infected cases had greatly increased hospital stay (P<0.001), were 4.5 times less likely to survive to discharge (P=0.002), and if they survived, were three times less likely to return to their original residence (P=0.05). The total cost of treatment per infected case was 24,410 pound sterling compared with 7210 pound sterling for controls (P<0.001). Meticillin-resistant Staphylococcus aureus (MRSA) infection increased admission length and cost compared with non-MRSA infection (P=0.02). Deep wound infection after PFF is a devastating and costly complication for both the patient and the healthcare services. The cost consequences should be considered when allocating resources to trauma services to ensure adequate provision to minimize infection risks and to accommodate treatment costs in this vulnerable group.

Perioperative fluid volume optimization following proximal femoral fracture

BACKGROUND

Proximal Femoral Fracture (PFF) or 'hip fracture' is a frequent injury, and adverse outcomes are common. Several factors suggest the importance of developing techniques to optimize intravascular fluid volume. These may include protocols that enhance the efficacy of clinicians' assessments, invasive techniques such as oesophageal Doppler or central venous pressure monitoring, or advanced non-invasive techniques such as plethysmographic pulse volume determination.

OBJECTIVES

To determine the optimal method of fluid volume optimization for adult patients undergoing surgical repair of PFF. Comparisons of fluid types, of blood transfusion strategies or of pharmacological interventions are not considered in this review.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library, issue 4, 2003), MEDLINE (1985 to 2003), EMBASE (1985 to 2003), and bibliographies of retrieved articles. Relevant journals and conference proceedings were handsearched.

SELECTION CRITERIA

Randomized controlled studies comparing a fluid optimization intervention with normal practice or with another fluid optimization intervention, in patients following PFF undergoing surgery of any type under anaesthesia of any type.

DATA COLLECTION AND ANALYSIS

Searches and exclusion of clearly irrelevant articles were performed by one reviewer. Two reviewers examined independently the remaining studies, extracting study quality and results data. A wide range of short- and long-term outcome data were sought. Studies were excluded if they did not meet selection criteria or if results were likely to be biased. Due to inconsistent data reporting, combination of data was not generally possible.

MAIN RESULTS

Searches identified four trials, of which two studies, randomizing a total of 130 patients, were of adequate quality and addressed the review question. Both studies were of invasive advanced haemodynamic monitoring, either oesophageal Doppler ultrasonography or central venous pressure monitoring, during the intraoperative period only. In both, invasive monitoring led to significant increases in fluid volumes infused and reductions in length of hospital stay. The pooled Peto odds ratio for in-hospital fatality was 1.44 (95% confidence interval 0.45-4.62). Neither study followed patients beyond hospital discharge or assessed functional outcomes. No serious complications were directly attributable to the interventions. There were no studies of protocol-guided fluid optimization or of advanced non-invasive techniques.

REVIEWER'S CONCLUSIONS

Invasive methods of fluid optimization during surgery may shorten hospital stay, but their effects on other important, patient-centred, longer-term outcomes are uncertain. Adverse effects on fatality cannot be excluded. Other fluid optimization techniques have not been evaluated. The lack of randomized studies of adequate quality addressing this important question is disappointing. More research is needed.

An N-of-1 randomized controlled trial ('N-of-1 trial') of donepezil in the treatment of non-progressive amnestic syndrome

INTRODUCTION

a professional man sustained a residual, persisting, isolated impairment of short-term memory secondary to severe carbon monoxide poisoning. Informal, open trial of the cholinesterase inhibitor donepezil resulted in uncertain benefit.

PROTOCOL

an N-of-1 randomized, double-blind controlled trial of donepezil against placebo. Placebo-induced headache permitted evaluation of donepezil at only the 5 mg dose.

RESULTS

there was no improvement in short-term memory.

CONCLUSION

the trial excluded significant benefit of donepezil 5 mg in this patient, preventing long-term unnecessary prescription. Beneficial effects in other similar patients or at higher dosage cannot be excluded.

Subjective barriers to prevent wandering of cognitively impaired people

BACKGROUND

People with dementia often wander, at times putting themselves at risk and presenting challenges to carers and institutional staff. Traditional interventions to prevent wandering include restraint, drugs and locked doors. Cognitively impaired people may respond to environmental stimuli (sounds, images, smells) in ways distinct from healthy people. This has led to trials of visual and other selective barriers (such as mirrors, camouflage, grids/stripes of tape) that may reduce wandering.

OBJECTIVES

We assess the effect of subjective exit modifications on the wandering behaviour of cognitively impaired people. The second objective is to inform the direction and methods of future research.

SEARCH STRATEGY

The search strategy includes electronic searches of relevant bibliographic and trials databases, citation indices and relevant medical journals.

SELECTION CRITERIA

Randomized controlled trials and controlled trials provide the highest quality evidence, but interrupted time series are also considered as they may contribute useful information. Participants are people with dementia or cognitive impairment who wander, of any age, and in any care environment - hospital, other institution, or their own home. Interventions comprise exit modifications that aim to function as subjective barriers to prevent the wandering of cognitively impaired people. Locks, physical restraints, electronic tagging and other types of barrier are not included.

DATA COLLECTION AND ANALYSIS

The criteria for inclusion or exclusion of studies are applied independently by two reviewers. All outcomes that are meaningful to people making decisions about the care of wanderers are recorded. These include the number of exits or carer interventions, resource use, acceptability of the intervention and the effects on carer and wanderer anxiety or distress. heterogeneity of clinical area, of study design and of intervention was substantial.

MAIN RESULTS

No randomized controlled or controlled trials were found. The other experimental studies that we identified were unsatisfactory. Most were vulnerable to bias, particularly performance bias; most did not classify patients according to type or severity of dementia; in all studies, outcomes were measured only in terms of wandering frequency rather than more broadly in terms of quality of life, resource use, anxiety and distress; no studies included patients with delirium; no studies were based in patients' homes.

REVIEWER'S CONCLUSIONS

There is no evidence that subjective barriers prevent wandering in cognitively impaired people.