Impact of performance and information feedback on medical interns' confidence-accuracy calibration.

Diagnostic errors are a major, largely preventable, patient safety concern. Error interventions cannot feasibly be implemented for every patient that is seen. To identify cases at high risk of error, clinicians should have a good calibration between their perceived and actual accuracy. This experiment studied the impact of feedback on medical interns' calibration and diagnostic process. In a two-phase experiment, 125 medical interns from Dutch University Medical Centers were randomized to receive no feedback (control), feedback on their accuracy (performance feedback), or feedback with additional information on why a certain diagnosis was correct (information feedback) on 20 chest X-rays they diagnosed in a feedback phase. A test phase immediately followed this phase and had all interns diagnose an additional 10 X-rays without feedback. Outcome measures were confidence-accuracy calibration, diagnostic accuracy, confidence, and time to diagnose. Both feedback types improved overall confidence-accuracy calibration (R2No Feedback = 0.05, R2Performance Feedback = 0.12, R2Information Feedback = 0.19), in line with the individual improvements in diagnostic accuracy and confidence. We also report secondary analyses to examine how case difficulty affected calibration. Time to diagnose did not differ between conditions. Feedback improved interns' calibration. However, it is unclear whether this improvement reflects better confidence estimates or an improvement in accuracy. Future research should examine more experienced participants and non-visual specialties. Our results suggest that feedback is an effective intervention that could be beneficial as a tool to improve calibration, especially in cases that are not too difficult for learners.

Improving selection procedures in health professions education from the applicant perspective: an interview study.

INTRODUCTION: Applicant perceptions of selection impact motivation and performance during selection, and student diversity. However, in-depth insight into which values underly these perceptions is lacking, creating challenges for aligning selection procedures with applicant perceptions. This qualitative interview study aimed to identify values applicants believe should underlie selection, and how, according to applicants, these values should be used to make specific improvements to selection procedures in undergraduate health professions education (HPE). METHODS: Thirty-one applicants to five undergraduate HPE programs in the Netherlands participated in semi-structured interviews using Appreciative Inquiry, an approach that focuses on what goes well to create vision for improvement, to guide the interviews. Transcriptions were analyzed using thematic analysis, adopting a constructivist approach. RESULTS: Applicants' values related to the aims of selection, the content of selection, and the treatment of applicants. Applicants believed that selection procedures should aim to identify students who best fit the training and profession, and generate diverse student populations to fulfill societal needs. According to applicants, the content of selection should be relevant for the curriculum and profession, assess a comprehensive set of attributes, be of high quality, allow applicants to show who they are, and be adapted to applicants' current developmental state. Regarding treatment, applicants believed that selection should be a two-way process that fosters reflection on study choice, be transparent about what applicants can expect, safeguard applicants' well-being, treat all applicants equally, and employ an equitable approach by taking personal circumstances into account. Applicants mentioned specific improvements regarding each value. DISCUSSION: Applicants' values offer novel insights into what they consider important preconditions for the design of selection procedures. Their suggested improvements can support selection committees in better meeting applicants' needs.

Does formative assessment help students to acquire prescribing skills?

PURPOSE: Formative assessments can help motivate students and ease students' learning through feedback. There is a pressing need for improvement of clinical pharmacotherapy (CPT) education since junior doctors make many prescribing errors. The aim of this study was to determine whether a formative assessment with personalized narrative feedback helps medical students to increase their prescribing skills. METHODS: This retrospective cohort study was conducted among masters' medical students at Erasmus Medical Centre, The Netherlands. Students made a formative and a summative skill-based prescription assessment, both during clerkships as part of their regular curriculum. Errors in both assessments were categorized by type and possible consequence and compared with each other. RESULTS: A total of 388 students made 1964 errors in the formative assessment and 1016 in the summative assessment. Most improvements after the formative assessment were seen for mentioning the weight of a child on the prescription (n = 242, 19%). Most new and repeated errors in the summative assessment were missing usage instructions (n = 82, 16% and n = 121, 41%). CONCLUSIONS: This formative assessment with personalized and individual narrative feedback has helped students to increase the technical correctness of their prescriptions. However, errors repeated after the feedback were predominantly errors showing that only one formative assessment has not yet enhanced the clinical prescribing enough.

Selection tools and student diversity in health professions education: a multi-site study.

Student diversity in health professions education (HPE) can be affected by selection procedures. Little is known about how different selection tools impact student diversity across programs using different combinations of traditional and broadened selection criteria. The present multi-site study examined the chances in selection of subgroups of applicants to HPE undergraduate programs with distinctive selection procedures, and their performance on corresponding selection tools. Probability of selection of subgroups (based on gender, migration background, prior education, parental education) of applicants (N = 1935) to five selection procedures of corresponding Dutch HPE undergraduate programs was estimated using multilevel logistic regression. Multilevel linear regression was used to analyze performance on four tools: prior-education grade point average (pe-GPA), biomedical knowledge test, curriculum-sampling test, and curriculum vitae (CV). First-generation Western immigrants and applicants with a foreign education background were significantly less likely to be selected than applicants without a migration background and with pre-university education. These effects did not vary across programs. More variability in effects was found between different selection tools. Compared to women, men performed significantly poorer on CVs, while they had higher scores on biomedical knowledge tests. Applicants with a non-Western migration background scored lower on curriculum-sampling tests. First-generation Western immigrants had lower CV-scores. First-generation university applicants had significantly lower pe-GPAs. There was a variety in effects for applicants with different alternative forms of prior education. For curriculum-sampling tests and CVs, effects varied across programs. Our findings highlight the need for continuous evaluation, identifying best practices within existing tools, and applying alternative tools.

The added value of free preparatory activities for widening access to medical education: a multi-cohort study.

BACKGROUND: Medical schools are reported to be less accessible to students with non-traditional backgrounds. These students face barriers when applying for and transitioning to medical school, which may be reduced by offering free preparatory activities. By equalizing access to resources, these activities are expected to reduce disparities in selection outcomes and early academic performance. In the present study, four free institutionally-provided preparatory activities were evaluated by comparing the demographic composition of participating and non-participating applicants. Additionally, the association between participation and selection outcomes and early academic performance was investigated for subgroups (based on sex, migration background and parental education). METHODS: Participants were applicants to a Dutch medical school in 2016-2019 (N = 3592). Free preparatory activities included Summer School (N = 595), Coaching Day (N = 1794), Pre-Academic Program (N = 217), and Junior Med School (N = 81), supplemented with data on participation in commercial coaching (N = 65). Demographic compositions of participants and non-participants were compared using chi-squared tests. Regression analyses were performed to compare selection outcomes (curriculum vitae [CV], selection test score, probability of enrolment) and early academic performance (first-course grade) between participants and non-participants of demographic subgroups, controlling for pre-university grades and participation in other activities. RESULTS: Generally, no differences in sociodemographic compositions of participants and non-participants were found, but males participated less often in Summer School and Coaching Day. Applicants with a non-Western background participated less often in commercial coaching, but the overall participation rate was low and participation had negligible effects on selection outcomes. Participation in Summer School and Coaching Day were stronger related with selection outcomes. In some cases, this association was even stronger for males and candidates with a migration background. After controlling for pre-university grades, none of the preparatory activities were positively associated with early academic performance. CONCLUSIONS: Free institutionally-provided preparatory activities may contribute to student diversity in medical education, because usage was similar across sociodemographic subgroups, and participation was positively associated with selection outcomes of underrepresented and non-traditional students. However, since participation was not associated with early academic performance, adjustments to activities and/or curricula are needed to ensure inclusion and retention after selection.

The eHealth self-management application 'Oncokompas' that supports cancer survivors to improve health-related quality of life and reduce symptoms: which groups benefit most?

BACKGROUND: Oncokompas is a web-based self-management application that supports cancer survivors to monitor their health-related quality of life (HRQOL) and symptoms, and to obtain personalised feedback and tailored options for supportive care. In a large randomised controlled trial among survivors of head and neck cancer, colorectal cancer, and breast cancer and (non-)Hodgkin lymphoma, Oncokompas proved to improve HRQOL, and to reduce several tumour-specific symptoms. Effect sizes were however small, and no effect was observed on the primary outcome patient activation. Therefore, this study aims to explore which subgroups of cancer survivors may especially benefit from Oncokompas. MATERIALS AND METHODS: Cancer survivors (n = 625) were randomly assigned to the intervention group (access to Oncokompas, n = 320) or control group (6 months waiting list, n = 305). Outcome measures were HRQOL, tumour-specific symptoms, and patient activation. Potential moderators included socio-demographic (sex, age, marital status, education, employment), clinical (tumour type, stage, time since diagnosis, treatment modality, comorbidities), and personal factors (self-efficacy, personal control, health literacy, Internet use), and patient activation, mental adjustment to cancer, HRQOL, symptoms, and need for supportive care, measured at baseline. Linear mixed models were performed to investigate potential moderators. RESULTS: The intervention effect on HRQOL was the largest among cancer survivors with low to moderate self-efficacy, and among those with high personal control and those with high health literacy scores. Cancer survivors with higher baseline symptom scores benefitted more on head and neck (pain in the mouth, social eating, swallowing, coughing, trismus), and colorectal cancer (weight) specific symptoms. DISCUSSION: Oncokompas seems most effective in reducing symptoms in head and neck cancer and colorectal cancer survivors who report a higher burden of tumour-specific symptoms. Oncokompas seems most effective in improving HRQOL in cancer survivors with lower self-efficacy, and in cancer survivors with higher personal control, and higher health literacy.

The relationship between time to diagnose and diagnostic accuracy among internal medicine residents: a randomized experiment.

BACKGROUND: Diagnostic errors have been attributed to cognitive biases (reasoning shortcuts), which are thought to result from fast reasoning. Suggested solutions include slowing down the reasoning process. However, slower reasoning is not necessarily more accurate than faster reasoning. In this study, we studied the relationship between time to diagnose and diagnostic accuracy. METHODS: We conducted a multi-center within-subjects experiment where we prospectively induced availability bias (using Mamede et al.'s methodology) in 117 internal medicine residents. Subsequently, residents diagnosed cases that resembled those bias cases but had another correct diagnosis. We determined whether residents were correct, incorrect due to bias (i.e. they provided the diagnosis induced by availability bias) or due to other causes (i.e. they provided another incorrect diagnosis) and compared time to diagnose. RESULTS: We did not successfully induce bias: no significant effect of availability bias was found. Therefore, we compared correct diagnoses to all incorrect diagnoses. Residents reached correct diagnoses faster than incorrect diagnoses (115 s vs. 129 s, p < .001). Exploratory analyses of cases where bias was induced showed a trend of time to diagnose for bias diagnoses to be more similar to correct diagnoses (115 s vs 115 s, p = .971) than to other errors (115 s vs 136 s, p = .082). CONCLUSIONS: We showed that correct diagnoses were made faster than incorrect diagnoses, even within subjects. Errors due to availability bias may be different: exploratory analyses suggest a trend that biased cases were diagnosed faster than incorrect diagnoses. The hypothesis that fast reasoning leads to diagnostic errors should be revisited, but more research into the characteristics of cognitive biases is important because they may be different from other causes of diagnostic errors.

A randomized clinical trial comparing two two-phase treatment strategies for in-patients with severe depression.

OBJECTIVE: To compare the efficacy of two antidepressant treatment strategies in severely depressed in-patients, that is, imipramine vs. venlafaxine, both with subsequent lithium addition in non-responders. METHOD: In-patients (n = 88) with major depressive disorder were randomized to 7-week treatment with imipramine or venlafaxine (phase I). All non-responders (n = 44) received 4-week plasma level-targeted dose lithium addition (phase II). Efficacy was evaluated after 11 weeks of treatment. RESULTS: Analyzing phases I and II combined, non-inferiority was established and the difference in the proportion of responders (HAM-D score reduction ≥50%) by the end of phase II demonstrated the venlafaxine-lithium treatment strategy to be significantly superior to the imipramine-lithium treatment strategy (77% vs. 52%) (χ2 (1) = 6.03; P = 0.01). Regarding remission (HAM-D score ≤ 7), 15 of 44 (34%) patients in the imipramine-lithium treatment group were remitters compared to 22 of 44 (50%) patients in the venlafaxine-lithium treatment group, a non-significant difference. Patients in the venlafaxine-lithium treatment group had a non-significant larger mean HAM-D score reduction compared with patients in the imipramine-lithium treatment group (16.1 vs. 13.5 points, respectively; Cohen's d = 0.30). CONCLUSION: The venlafaxine-lithium treatment strategy can be considered a valuable alternative for the imipramine-lithium treatment strategy in the treatment of severely depressed in-patients.

Gradient flipping algorithm: introducing non-convex constraints in wavefront reconstructions with the transport of intensity equation.

The transport of intensity equation (TIE) is widely applied for recovering wave fronts from an intensity measurement and a measurement of its variation along the direction of propagation. In order to get around the problem of non-uniqueness and ill-conditionedness of the solution of the TIE in the very common case of unspecified boundary conditions or noisy data, additional constraints to the solution are necessary. Although from a numerical optimization point of view, convex constraint as imposed to by total variation minimization is preferable, we will show that in many cases non-convex constraints are necessary to overcome the low-frequency artifacts so typical for convex constraints. We will provide simulated and experimental examples that demonstrate the superiority of solutions to the TIE obtained by our recently introduced gradient flipping algorithm over a total variation constrained solution.

Mild desalination of various raw water streams.

For chemical industries, fresh water availability is a pre-requisite for sustainable operation. However, in many delta areas around the world, fresh water is scarce. Therefore, the E4 Water project (www.e4water.eu) comprises a case study at the Dow site in Terneuzen, The Netherlands, which is designed to develop commercial applications for mild desalination of brackish raw water streams from various origins to enable reuse in industry or agriculture. This study describes an effective two-stage work process, which was used to narrow down a broad spectrum of desalination technologies to a selection of the most promising techniques for a demonstration pilot at 2-4 m³/hour. Through literature study, laboratory experiments and multi-criteria analysis, nanofiltration and electrodialysis reversal were selected, both having the potential to attain the objectives of E4Water at full scale.

Beta-blocking agents during electroconvulsive therapy: a review.

Electroconvulsive therapy (ECT) is associated with at least transient episodes of hypertension and tachycardia. Beta-blocking agents may be indicated to prevent cardiovascular complications and may shorten seizure duration. This review evaluates studies that used beta-blocking agents during ECT to determine which agent has the most favourable outcomes on cardiovascular variables and seizure duration. A Medline database search was made using the combined keywords 'adrenergic beta-antagonists' and 'electroconvulsive therapy'. The search was restricted to double-blind randomized controlled trials and yielded 29 original studies. With the use of esmolol, significant attenuating effects were found on cardiovascular parameters in the first 5 min after stimulation; its shortening effects on seizure duration may be dose-related. With the use of labetalol, findings on cardiovascular effects were inconsistent during the first minutes after stimulation but were significant after 5 min and thereafter; seizure duration was scarcely studied. Landiolol attenuates heart rate but with inconsistent findings regarding arterial pressure (AP); seizure duration was mostly unaffected. Esmolol appears to be effective in reducing the cardiovascular response, although seizure duration may be affected with higher dosages. Landiolol can be considered a suitable alternative, but effects on AP need further investigation. Labetalol has been studied to a lesser extent and may have prolonged cardiovascular effects. The included studies varied in design, methodology, and the amount of exact data provided in the publications. Further study of beta-blocking agents in ECT is clearly necessary.

The impact of patient-reported frailty on cardiovascular outcomes in elderly patients after non-ST-acute coronary syndrome.

BACKGROUND: As life expectancy increases, the population of older individuals with coronary artery disease and frailty is growing. We aimed to assess the impact of patient-reported frailty on the treatment and prognosis of elderly early survivors of non-ST-elevation acute coronary syndrome (NSTE-ACS). METHODS: Frailty data were obtained from two prospective trials, POPular Age and the POPular Age Registry, which both assessed elderly NSTE-ACS patients. Frailty was assessed one month after admission with the Groningen Frailty Indicator (GFI) and was defined as a GFI-score of 4 or higher. In these early survivors of NSTE-ACS, we assessed differences in treatment and 1-year outcomes between frail and non-frail patients, considering major adverse cardiovascular events (MACE, including cardiovascular mortality, myocardial infarction, and stroke) and major bleeding. RESULTS: The total study population consisted of 2192 NSTE-ACS patients, aged ≥70 years. The GFI-score was available in 1320 patients (79 ± 5 years, 37% women), of whom 712 (54%) were considered frail. Frail patients were at higher risk for MACE than non-frail patients (9.7% vs. 5.1%, adjusted hazard ratio [HR] 1.57, 95% confidence interval [CI] 1.01-2.43, p = 0.04), but not for major bleeding (3.7% vs. 2.8%, adjusted HR 1.23, 95% CI 0.65-2.32, p = 0.53). Cubic spline analysis showed a gradual increase of the risk for clinical outcomes with higher GFI-scores. CONCLUSIONS: In elderly NSTE-ACS patients who survived 1-month follow-up, patient-reported frailty was independently associated with a higher risk for 1-year MACE, but not with major bleeding. These findings emphasize the importance of frailty screening for risk stratification in elderly NSTE-ACS patients.

Abnormal myotonic dystrophy protein kinase levels produce only mild myopathy in mice.

Myotonic dystrophy (DM) is commonly associated with CTG repeat expansions within the gene for DM-protein kinase (DMPK). The effect of altered expression levels of DMPK, which is ubiquitously expressed in all muscle cell lineages during development, was examined by disrupting the endogenous Dmpk gene and overexpressing a normal human DMPK transgene in mice. Nullizygous (-/-) mice showed only inconsistent and minor size changes in head and neck muscle fibres at older age, animals with the highest DMPK transgene expression showed hypertrophic cardiomyopathy and enhanced neonatal mortality. However, both models lack other frequent DM symptoms including the fibre-type dependent atrophy, myotonia, cataract and male-infertility. These results strengthen the contention that simple loss- or gain-of-expression of DMPK is not the only crucial requirement for development of the disease.

Reasons for not reaching or using web-based self-management applications, and the use and evaluation of Oncokompas among cancer survivors, in the context of a randomised controlled trial.

INTRODUCTION: The web-based self-management application Oncokompas was developed to support cancer survivors to monitor health-related quality of life and symptoms (Measure) and to provide tailored information (Learn) and supportive care options (Act). In a previously reported randomised controlled trial (RCT), 68% of 655 recruited survivors were eligible, and of those 45% participated in the RCT. Among participants of the RCT that were randomised to the intervention group, 52% used Oncokompas as intended. The aim of this study was to explore reasons for not participating in the RCT, and reasons for not using Oncokompas among non-users, and the use and evaluation of Oncokompas among users. METHODS: Reasons for not participating were assessed with a study-specific questionnaire among 243 survivors who declined participation. Usage was investigated among 320 participants randomised to the intervention group of the RCT via system data and a study-specific questionnaire that was assessed during the 1 week follow-up (T1) assessment. RESULTS: Main reasons for not participating were not interested in participation in scientific research (40%) and not interested in scientific research and Oncokompas (28%). Main reasons for not being interested in Oncokompas were wanting to leave the period of being ill behind (29%), no symptom burden (23%), or lacking internet skills (18%). Out of the 320 participants in the intervention group 167 (52%) used Oncokompas as intended. Among 72 non-users, main reasons for not using Oncokompas were no symptom burden (32%) or lack of time (26%). Among 248 survivors that activated their account, satisfaction and user-friendliness were rated with a 7 (scale 0-10). Within 3 (IQR 1-4) sessions, users selected 32 (IQR 6-37) topics. Main reasons for not using healthcare options in Act were that the information in Learn was already sufficient (44%) or no supportive care needs (32%). DISCUSSION: Main reasons for not reaching or using Oncokompas were no symptom burden, no supportive care needs, or lack of time. Users selected many cancer-generic and tumour-specific topics to address, indicating added value of the wide range of available topics.

Cost-utility of an eHealth application 'Oncokompas' that supports cancer survivors in self-management: results of a randomised controlled trial.

PURPOSE: The eHealth self-management application 'Oncokompas' was developed to support cancer survivors in monitoring health-related quality of life (HRQOL) and symptoms, and obtaining personalized feedback and options for supportive care. The aim of this study was to assess the cost-utility of Oncokompas compared with care as usual (CAU) among cancer survivors. METHODS: Survivors were randomly allocated to the intervention or control group. Direct (non-)medical, indirect non-medical costs, and HRQOL were measured at 3- and 6-month follow-up, using iMTA Medical Consumption and Productivity Costs and the EuroQol-5D questionnaires. Mean cumulative costs and quality-adjusted life-years (QALYs) were compared between both groups. RESULTS: In total, 625 survivors were randomized into intervention (n = 320) or control group (n = 305). Base case analysis showed that incremental costs from a societal perspective were - €163 (95% CI, - 665 to 326), and incremental QALYs were 0.0017 (95% CI, - 0.0121 to 0.0155) in the intervention group compared with those in the control group. The probability that, compared with CAU, Oncokompas is more effective was 60%, less costly 73%, and both more effective and less costly 47%. Sensitivity analyses showed that incremental costs vary between - €40 and €69, and incremental QALYs vary between - 0.0023 and - 0.0057. CONCLUSION: Oncokompas is likely to be equally effective on utilities, and not more expensive than CAU, and will therefore contribute to sustainable cancer survivorship care in a (cost-)effective manner. IMPLICATIONS FOR CANCER SURVIVORS: Oncokompas seems to improve HRQOL and reduces the burden of several tumour-specific symptoms, while costs from a societal perspective are similar to CAU.

Treatment of unipolar psychotic depression: a randomized, double-blind study comparing imipramine, venlafaxine, and venlafaxine plus quetiapine.

OBJECTIVE: It remains unclear whether unipolar psychotic depression should be treated with an antidepressant and an antipsychotic or with an antidepressant alone. METHOD: In a multi-center RCT, 122 patients (18-65 years) with DSM-IV-TR psychotic major depression and HAM-D-17 > or = 18 were randomized to 7 weeks imipramine (plasma-levels 200-300 microg/l), venlafaxine (375 mg/day) or venlafaxine-quetiapine (375 mg/day, 600 mg/day). Primary outcome was response on HAM-D-17. Secondary outcomes were response on CGI and remission (HAM-D-17). RESULTS: Venlafaxine-quetiapine was more effective than venlafaxine with no significant differences between venlafaxine-quetiapine and imipramine, or between imipramine and venlafaxine. Secondary outcomes followed the same pattern. CONCLUSION: That unipolar psychotic depression should be treated with a combination of an antidepressant and an antipsychotic and not with an antidepressant alone, can be considered evidence based with regard to venlafaxine-quetiapine vs. venlafaxine monotherapy. Whether this is also the case for imipramine monotherapy is likely, but cannot be concluded from the data.

Optimization of a FIB/SEM slice-and-view study of the 3D distribution of Ni4Ti3 precipitates in Ni-Ti.

The 3D morphology and distribution of lenticular Ni(4)Ti(3) precipitates in the austenitic B2 matrix of a binary Ni(51)Ti(49) alloy has been investigated by a slice-and-view procedure in a dual-beam focused ion beam/scanning electron microscope system. Due to the weak contrast of the precipitates, proper imaging conditions need to be selected first to allow for semi-automated image treatment. Knowledgeable imaging is further needed to ensure that all variants of the precipitates are observed with equal probability, regardless of sample orientation. Finally, a volume ratio of 10.2% for the Ni(4)Ti(3) precipitates could be calculated, summed over all variants, which yields a net composition of Ni(50.27)Ti(49.73) for the matrix, leading to an increase of 125 degrees for the martensitic start temperature. Also, the expected relative orientation of the different variants of the precipitates could be confirmed.

Efficacy of venlafaxine compared with tricyclic antidepressants in depressive disorder: a meta-analysis.

With respect to the pharmacological characteristic, venlafaxine is comparable with tricyclic antidepressants (TCAs), and venlafaxine might be comparable in efficacy. We performed a systematic review investigating the relative efficacy and tolerability of venlafaxine compared with TCAs (imipramine, clomipramine, amitriptyline, nortriptyline and desipramine). Relevant double-blind randomised trials were identified from systematic searches of electronic databases. An exact analysis of the estimated odds ratios of response of the TCA relative to venlafaxine showed no overall significance of treatment effect (P = 0.38). The odds ratios were not homogenous across studies (P = 0.0213). The average dose of venlafaxine was 103.5 mg/day and for the TCA 106.1 mg/day. An exact analysis of the estimated odds ratios of the withdrawals and side effects in the trials with a TCA relative to venlafaxine showed no overall significance of withdrawal. From our review, no significant difference in treatment effect between low dose of both venlafaxine and the TCAs could be found. In our opinion, because of the heterogeneity of the odds ratios, one cannot conclude that they are of equal efficacy.

Tomographic spectroscopic imaging; an experimental proof of concept.

Recording the electron energy loss spectroscopy data cube with a series of energy filtered images is a dose inefficient process because the energy slit blocks most of the electrons. When recording the data cube by scanning an electron probe over the sample, perfect dose efficiency is attained; but due to the low current in nanoprobes, this often is slower, with a smaller field of view. In W. Van den Broek et al. [Ultramicroscopy, 106 (2006) 269], we proposed a new method to record the data cube, which is more dose efficient than an energy filtered series. It produces a set of projections of the data cube and then tomographically reconstructs it. In this article, we demonstrate these projections in practice, we present a simple geometrical model that allows for quantification of the projection angles and we present the first successful experimental reconstruction, all on a standard post-column instrument.