Comparing the Effectiveness of Two Therapies to Treat Signs of Anorexia Nervosa in Adolescents: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Comparing the Effectiveness of Two Therapies to Treat Signs of Anorexia Nervosa in Adolescents (NCT00418977), a randomized na study. The primary outcome is Body Mass Index (BMI) Z-score.

2. Clinical Question

3. Trial Design

The registry describes a randomized, parallel-group behavioral therapy study with no masking. It lists an enrollment of 59 and identifies Icahn School of Medicine at Mount Sinai as the sponsor. The record gives a study start of 2005-09, a primary completion date of 2011-08, and a status of COMPLETED. The phase is listed as NA, which is consistent with a behavioral therapy study rather than a drug-phase designation.

The two treatment arms were Family Based Therapy and Individual Supportive Psychotherapy. The registry’s arm descriptions say participants would receive the named therapy; more detailed information about treatment delivery, treatment duration, therapist qualifications, adherence, or co-interventions is not reported in the registry record. The intended population is adolescents with early signs of anorexia nervosa, but specific eligibility criteria and the age distribution of enrolled participants are not reported.

The arm-level outcome summaries list 40 participants for Family Based Therapy and 13 for Individual Supportive Psychotherapy for the primary measure. These outcome counts are not the same as the overall enrollment figure. Reasons for the difference, including the number randomized, numbers assessed at each time, withdrawals, and missing outcome data, are not reported in the registry record. The record does not provide a participant flow account that would explain how enrollment relates to the analysis counts.

The primary outcome timeframe is up to 1 year. The record does not specify the precise assessment schedule within that timeframe or identify a single visit used for the posted summary. It lists height, weight, BMI, and BMI percentile as secondary outcomes. Additional information about the trial’s original sample-size justification, allocation procedures, and prespecified statistical plan is not reported in the registry record.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Body Mass Index (BMI) Z-score, measured over up to 1 year.

The primary endpoint is mean Body Mass Index (BMI) Z-score, a continuous measure reported in z-score units. A BMI z-score expresses BMI relative to a reference distribution, so it describes a participant’s position in that reference context rather than BMI in kg/m^2 itself. The registry says the z-score was calculated using the Baylor College of Medicine Children's Nutrition Research Center's online BMI calculator. The specific reference inputs and implementation details are not reported in the registry record.

Reporting a mean allows the registry to describe the average outcome in each treatment arm and compare those averages. The standard deviation describes how dispersed individual values were around each arm’s mean. These summaries convey both the central tendency and the variability of a continuous endpoint, but they do not show the full distribution or how each participant changed over time.

The listed timeframe is up to 1 year. The registry does not say whether the posted values represent change from baseline, an endpoint value, an average across assessments, or another summary over that period. That distinction matters: a difference in mean endpoint values is not automatically a difference in change from baseline. The available record supports describing the posted means and their comparison, but not inferring an unreported baseline-adjusted or longitudinal analysis.

BMI z-score is used as the primary measure because it places BMI in a standardized reference context. That general statistical rationale does not establish which clinical interpretation is appropriate for an individual. The registry does not give a threshold for a meaningful difference, and the posted mean difference should be read as a statistical contrast in the recorded units rather than as a stand-alone clinical conclusion.

7. Results Posted in the Registry

• Individual Supportive Psychotherapy: mean -0.02 versus -0.72 on control; difference 0.70 (95% CI 0.10 to 1.30), standardized effect d = 0.72; z-test p = 0.021.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Height

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Individual Supportive Psychotherapy: mean 63.60 versus 61.30 on control; difference 2.30 (95% CI -0.36 to 4.96), standardized effect d = 0.50; z-test p = 0.090.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Individual Supportive Psychotherapy and the control. The interval gives the range of effects that remain compatible with the data.

Weight

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Individual Supportive Psychotherapy: mean 114.70 versus 94.90 on control; difference 19.80 (95% CI 2.69 to 36.91), standardized effect d = 0.85; z-test p = 0.023.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Individual Supportive Psychotherapy than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

BMI

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Individual Supportive Psychotherapy: mean 19.70 versus 17.60 on control; difference 2.10 (95% CI 0.36 to 3.84), standardized effect d = 0.92; z-test p = 0.018.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Individual Supportive Psychotherapy than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The registry names height, weight, BMI, and BMI percentile as secondary outcomes. The posted secondary summaries include height, weight, and BMI. Across those posted measures, the mean values are higher in the Individual Supportive Psychotherapy arm than in the Family Based Therapy arm. This broad directional pattern is consistent with the positive direction of the primary BMI z-score comparison, but the measures are related rather than independent confirmations of the same endpoint.

Height, weight, BMI, BMI percentile, and BMI z-score describe different aspects or representations of body size. They should not be treated as interchangeable outcomes. In particular, the primary measure is a standardized BMI score, whereas the posted secondary BMI is expressed in kg/m^2. The registry does not provide a numerical BMI percentile comparison, so its direction and precision cannot be assessed from the recorded secondary results.

The secondary comparisons are unadjusted and the registry reports no analyses for them. Their p-values therefore do not establish confirmatory findings. General statistical explanation: when many outcomes or comparisons are examined, the chance of observing at least one apparently notable result by chance can increase. Adjustments or a prespecified hierarchy can address some multiplicity concerns, but the registry does not report whether either was used. These secondary results consequently carry less evidential weight than a clearly prespecified primary analysis, and even the primary analysis details are not reported.

The pattern can be described as directionally aligned across the posted secondary measures, but this should not be taken as several independent replications. Measures such as weight and BMI are related, and their errors and changes may be correlated. The record does not give participant-level correlations or a joint analysis. The secondary data add context to the primary result, while leaving questions about multiplicity, missingness, and clinical interpretation unresolved.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Height
• Weight
• BMI
• BMI Percentile

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is continuous, so the registry reports a mean and standard deviation for each arm. The mean is the arithmetic average of the recorded values. The standard deviation describes the spread of participant values around that average. In general, a mean difference compares the average in one group with the average in another, while preserving the units of the outcome. Here the contrast is expressed in BMI z-score units and is oriented as Individual Supportive Psychotherapy compared with Family Based Therapy.

What does the mean difference represent?

The posted means are -0.72 for Family Based Therapy and -0.02 for Individual Supportive Psychotherapy. The reported comparison is 0.7. This is an unadjusted difference between the arm means, not an estimate adjusted for baseline values or other participant characteristics. The registry does not report whether the values are endpoint means, changes from baseline, or another summary within the up-to-1-year timeframe. General statistical interpretation of a difference depends on the outcome definition and the analysis population, both of which should be kept in view.

What do standard deviations and standard errors tell us?

A standard deviation describes variation among individual observations within an arm. A standard error describes uncertainty in an estimated statistic, such as a group mean, and is generally smaller when there is more information, assuming the other features of the data remain comparable. The primary arm standard deviations are 0.99 and 0.94. The reported standard errors of the means are 0.157 and 0.261. The standard error is not another measure of participant-to-participant variation; it describes the precision of the estimated mean.

General statistical reasoning also explains why unequal group sizes matter. With fewer observations, an estimated mean tends to have greater sampling uncertainty, all else being equal. The outcome counts are 40 and 13, so the estimates do not have equal precision. The registry does not explain the relationship between these outcome counts, the enrollment of 59, and the number of participants randomized or assessed.

How should the confidence interval be read?

A confidence interval expresses uncertainty around an estimate under the statistical method used. The interval for the primary mean difference is 0.104 to 1.296. In general, a confidence interval is not a guarantee that the true value lies within its endpoints, nor does it account for design limitations or unreported sources of bias. It describes sampling uncertainty under assumptions, and its interpretation depends on the analysis method and data being appropriate for that method.

The interval shown is based on a simple unadjusted comparison calculated from the posted summary statistics. The registry reports no primary analysis, so the interval should not be represented as a sponsor-reported model result. The comparison’s unadjusted p-value is 0.021. A p-value is a probability calculated under a null model and specified assumptions; it is not the probability that the null hypothesis is true, nor a measure of the size or importance of an effect.

Why can over-dispersion matter?

General explanation: over-dispersion occurs when observed variability is greater than a statistical model expects. If a model understates variability, standard errors may be too small and intervals too narrow, making the evidence appear more precise than it is. The choice of model should reflect the outcome’s distribution and design. The registry record does not report a model-based analysis or information that would establish whether over-dispersion was assessed. The primary endpoint is continuous and the posted summaries include standard deviations, but those summaries alone do not reveal the full data distribution.

What does “unadjusted” mean in this comparison?

General explanation: an unadjusted comparison uses the group summaries without accounting for other variables, such as baseline outcome values or prognostic characteristics. Adjustment can be useful when specified and appropriately conducted, but it cannot be assumed from a mean difference alone. The registry does not report baseline BMI z-score values, covariate adjustment, or an analysis model. It is therefore important to describe the posted contrast as an unadjusted recalculation rather than to imply that it accounts for baseline imbalance or other factors.

Random allocation is intended in general to support a fair comparison by reducing systematic differences in expectation, but it does not ensure that groups will be identical in a particular study. The record says allocation was randomized; details of sequence generation, concealment, and implementation are not reported. No masking was used. Lack of masking can be relevant to how outcomes are assessed or reported, although the registry does not describe the assessment procedures or whether assessors knew participants’ assignments.

Finally, a statistical result does not describe all dimensions of evidence. Precision, analysis choices, missing data, multiplicity, and the relevance of the measured outcome all matter. The registry gives some outcome summaries and a simple comparison, but it does not report the full protocol or analysis plan. General statistical interpretation should therefore remain close to the posted data and avoid assumptions about unreported procedures.

11. Confidence Intervals and Precision

Precision is about how much uncertainty surrounds an estimate. For the primary mean difference of 0.7 BMI z-score units, the confidence interval extends from 0.104 to 1.296. The interval is entirely on the positive side of zero, while its span also shows that the exact size of the difference is not pinned down to a single value. The unadjusted p-value is 0.021, but the interval is more informative about the range of effect sizes compatible with the calculation than a threshold-based description alone.

These limits are calculated from the posted summary statistics and are not a reported adjusted model interval. They do not account for uncertainty about missing outcomes, possible departures from model assumptions, multiple comparisons, or limitations in trial conduct. The registry does not provide enough information to quantify those sources of uncertainty. The interval should therefore be interpreted as sampling precision for this simple comparison, not as a comprehensive measure of all uncertainty around the trial’s findings.

The arm counts are unequal: 40 for Family Based Therapy and 13 for Individual Supportive Psychotherapy. In general, smaller samples yield less precise estimates, other things being equal. The standard errors of the arm means are 0.157 and 0.261, respectively, consistent with greater uncertainty for the mean based on fewer participants. This does not explain why the recorded counts differ or identify whether any data are missing.

The confidence interval does not establish clinical importance. The registry does not report a threshold for a meaningful difference in BMI z-score. Nor does the interval answer whether the observed contrast persists beyond the stated timeframe of up to 1 year. It gives a statistical range for the posted comparison under its calculation, and interpretation beyond that depends on information the registry record does not report.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The sample-size estimates are planning illustrations based on the observed effect, not a report of the trial’s original design calculations. They assume a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is set at the stated fraction of the observed effect. The original trial’s sample-size assumptions and justification are not reported in the registry record.

Each entry for these continuous outcomes is expressed as participants per arm, not as a total across both arms and not as a total number of events. The columns for 80% and 90% power describe planning targets: under the stated assumptions, they indicate the approximate number of participants per arm needed for the calculation to have the corresponding chance of detecting the specified effect if that effect is real. A 90% target requires more participants than an 80% target for the same effect scenario.

The row labels describe planning for 100%, 75%, or 50% of the observed effect. These are hypothetical effect sizes for planning, not separate effects observed in the trial. As the assumed effect becomes smaller, more participants are needed to distinguish it from random variation at the same power target. This illustrates why planning around a smaller, more cautious effect estimate can require a larger study.

These values are not observed power. They do not measure the probability that the completed trial detected an effect after its results were known. They are hypothetical planning estimates using the stated calculation assumptions. Actual enrollment, unequal outcome counts, missing data, and analysis choices can differ from the simplified assumptions used for these illustrations.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = 0.700; pooled standard deviation σ = 0.978.
2. n = 2 × (1.96 + 0.842)² × 0.978² / 0.700² = 30.7, rounded up to 31 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- 0.7                      # observed difference in means
sigma <- 0.978465184688274                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(418977)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 31 (80% power), 42 (90% power)
 75% of observed effect: n per arm = 55 (80% power), 73 (90% power)
 50% of observed effect: n per arm = 123 (80% power), 165 (90% power)
power.t.test: 31.7 
Simulated power at n = 31 per arm: 0.793 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary outcome and several secondary outcomes, but it does not report a statistical analysis plan describing how conclusions were to be prioritized across them. The primary outcome is BMI Z-score. Height, weight, BMI, and BMI percentile are named as secondary outcomes. Whether there were additional planned comparisons, time points, or subgroup analyses is not reported in the registry record.

General explanation: multiplicity arises when several statistical tests are conducted. Without a planned approach, repeated testing can increase the chance that at least one result appears statistically notable even when there is no corresponding effect. Common strategies include adjusting significance thresholds or defining a hierarchy of outcomes, but the record does not report that either strategy was used. The posted secondary p-values are unadjusted and should be interpreted with that limitation in mind. The primary comparison’s p-value is also unadjusted in the recalculation.

The record indicates no reported analyses for the primary outcome and no reported analyses for the posted secondary outcomes. This means the registry record does not provide an analysis report; it does not establish that no analyses were performed elsewhere. The analysis population, including whether it was intention-to-treat, per-protocol, or another population, is not reported. The handling of participants who discontinued therapy or did not provide outcome data is also not reported.

Missing-data methods can affect estimates when some participants lack outcome measurements. General explanation: complete-case analyses use only participants with observed measurements, while other methods may use modeling or imputation assumptions. The appropriate approach depends on why data are missing and on the analysis plan. The registry does not describe missingness, reasons for missing values, imputation, or sensitivity analyses. The arm outcome counts differ, and the record does not explain that pattern.

Interim analyses, stopping rules, and any changes to the outcome definitions or analysis plan are not reported in the registry record. These absences limit assessment of how the analysis was chosen and how robust the posted results are to alternative decisions. They should be treated as reporting gaps rather than as evidence that any particular procedure was or was not followed.

15. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry’s adverse-event summaries list zero participants affected by serious adverse events in each arm: the at-risk counts are 43 for Family Based Therapy and 16 for Individual Supportive Psychotherapy. The summaries also list zero participants affected by other adverse events in each arm, using the same at-risk counts. These are event-reporting figures, distinct from the outcome counts used for the primary BMI z-score summaries.

Read these figures as the registry’s recorded counts for the specified adverse-event categories and at-risk groups. They do not establish that no unwanted experiences occurred outside the registry’s definitions or reporting process. The record does not list serious adverse-event terms, and it does not provide explanatory detail about collection, assessment, or follow-up of adverse events. Death counts are not reported in the registry record.

The at-risk counts differ from the primary outcome counts and from one another. The record does not explain the relationship between these denominators, enrollment, and the outcome populations. The figures should therefore be interpreted as the specific adverse-event summaries recorded, not as a complete safety analysis or a direct comparison of overall risk.

16. What the Result Does, and Does Not, Mean

The recorded primary comparison describes a higher mean BMI z-score in the Individual Supportive Psychotherapy arm than in the Family Based Therapy arm. The unadjusted mean difference is 0.7, with a confidence interval from 0.104 to 1.296 and an unadjusted p-value of 0.021. This is a statistical description of the posted outcome summaries, not a conclusion about what an individual participant will experience.

The result does not by itself show that one therapy is better overall. The registry reports one primary continuous outcome over a timeframe of up to 1 year, and it does not report the precise assessment schedule, change-from-baseline analysis, or adjusted model. The record also does not provide a threshold for a clinically meaningful difference. Statistical evidence against a zero mean difference and clinical importance are different questions.

The result also cannot be interpreted as evidence about outcomes not recorded, about persistence beyond the stated timeframe, or about all adolescents with anorexia nervosa. The intended population is adolescents with early signs of anorexia nervosa, but detailed eligibility criteria and participant characteristics are not reported. The observed arm counts are unequal, and the record does not explain how the outcome counts relate to enrollment or whether missing values affected the summaries.

The study was randomized, but details of allocation generation and concealment are not reported. There was no masking. These registry entries are relevant context, but the record does not give enough detail to assess how allocation was implemented or how outcomes were measured. A simple recalculation from arm summaries also cannot substitute for a full report of the prespecified analysis.

The posted secondary measures have a broadly similar direction, but they are related outcomes and their analyses are unadjusted. The registry does not report a multiplicity strategy or analysis hierarchy. Taken together, the record offers a comparison of observed summaries while leaving important questions about precision, missing data, analysis populations, and clinical meaning unanswered. Conclusions should remain limited to these posted data and their stated timeframe.

17. Why This Trial Matters Statistically

This trial illustrates why reading a treatment comparison involves more than looking at a p-value. The primary outcome is continuous, so the arm means and standard deviations describe both average levels and variability. The mean difference gives the direction and size of the observed contrast in the endpoint’s own units, while the confidence interval communicates uncertainty around that estimate.

The comparison also highlights the importance of denominators. Overall enrollment is 59, while the primary outcome summaries list 40 participants in one arm and 13 in the other. The adverse-event summaries use other at-risk counts. Those are not interchangeable populations, and the registry does not explain how participants moved from enrollment to each result. A careful reader notices this rather than assuming that every summary includes the same participants.

Another statistical issue is the relationship between a primary result and multiple secondary outcomes. The posted secondary outcomes point in a broadly similar direction, but related measures do not constitute independent replications. Because analysis and multiplicity procedures are not reported, unadjusted secondary findings should be treated as contextual rather than conclusive evidence.

The planning illustrations demonstrate how sample-size calculations depend on assumptions about the effect to be detected, power target, allocation, and statistical approximation. They are not the trial’s original justification and do not describe the completed study’s observed power. This distinction helps separate prospective planning from retrospective interpretation.

Finally, the record shows the limits of registry summaries. Randomization and a completed status are useful design information, but key details about the protocol, missing data, analysis population, and outcome timing are absent. Statistical interpretation is strongest when it distinguishes what the recorded numbers support from what would require additional information.

18. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

Several limitations specific to this trial affect interpretation of the posted result. The arm counts for the primary outcome are 40 and 13, while overall enrollment is 59. The record does not report how many participants were randomized, why the outcome counts differ, whether participants withdrew, or how missing outcomes were handled. This prevents a clear account of the analysis population and participant flow.

The registry gives a timeframe of up to 1 year but does not identify the exact measurement visit or say whether the primary summaries represent endpoint values, changes from baseline, or another summary. Baseline BMI z-scores and an adjusted analysis are not reported. Consequently, the simple mean comparison cannot be interpreted as a baseline-adjusted treatment contrast.

The study used no masking, and the registry does not describe who assessed outcomes or whether assessors knew treatment assignments. It also does not give detailed eligibility criteria, participant characteristics, therapy delivery information, adherence, or co-interventions. These omissions limit assessment of how representative the enrolled participants were and how consistently interventions were implemented.

The registry does not report an analysis plan, multiplicity strategy, analysis population, interim analyses, or original sample-size justification. No analyses are listed as reported for the primary or secondary outcomes. The secondary comparisons are unadjusted, and the numerical result for BMI percentile is not reported in the registry record despite BMI percentile being named as a secondary outcome.

Finally, the available summaries do not provide a threshold for clinical importance or evidence beyond the stated timeframe. These limitations do not negate the posted statistics; they define the scope of what those statistics can support. Additional trial documentation would be needed to resolve the unanswered design and analysis questions.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Comparing the Effectiveness of Two Therapies to Treat Signs of Anorexia Nervosa in Adolescents — NCT00418977.
• Registry record last updated 2015-12-23; status last verified 2015-11.
• Results first posted 2014-04-28.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

22. Record Summary

NCT00418977 is a completed randomized, parallel-group study with no masking, sponsored by Icahn School of Medicine at Mount Sinai. The record describes a comparison of Family-Based Therapy and Individual Supportive Psychotherapy for early signs of anorexia nervosa in adolescents, with enrollment of 59.

The primary outcome was mean BMI Z-score over up to 1 year. The posted summaries show an unadjusted mean difference of 0.7, with a confidence interval of 0.104 to 1.296 and an unadjusted p-value of 0.021, comparing Individual Supportive Psychotherapy with Family Based Therapy. Outcome counts were 40 and 13.

Height, weight, BMI, and BMI percentile are listed as secondary outcomes; numerical summaries are posted for height, weight, and BMI. The registry does not report an analysis plan, missing-data approach, analysis population, multiplicity procedure, or the trial’s original sample-size justification. The available results describe the recorded comparisons but do not resolve these reporting gaps.