This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Development of Method of Fructose Identification in Urine to Detect the Viral Infection (NCT01638312), a registered phase not stated study. The primary outcome is Fructose Identification in Urine to Detect the Viral Infection : Number of Participants With Positive and Negative Waveform.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01638312 |
| Phase | Phase not stated |
| Condition | Human Immunodeficiency Virus |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 50 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Kaohsiung Medical University Chung-Ho Memorial Hospital |
| Results posted | Yes |
2. Clinical Question
Population
People with HIV infection and healthy controls were included. The registry record describes 20 samples from HIV-infected patients and 30 from healthy controls; it does not provide further eligibility criteria or participant characteristics.
Intervention
There was no intervention. Participants provided a urine sample once, with 10ml collected for examination using a polarographic method.
Comparator
The comparison was between samples from people described as having HIV infection and samples from healthy controls. The record does not state how participants were assigned to these groups, and this is not described as a randomized comparison.
Primary question
Can fructose and fructose-diphosphate waveform measurements in urine distinguish samples classified as abnormal positive from those classified as normal negative, with the intended use of detecting viral infection at an early stage?
The study’s stated aim was to develop a fast and simple method based on electrochemistry. Its proposed signal is a voltage-related waveform associated in the registry description with fructose concentration and derivatives. A participant’s result was to be categorized using a σ threshold: σ >= 10 units was defined as abnormal positive, while σ < 10 units was defined as normal negative. The registry record does not describe an independent reference standard for establishing HIV status, or report how the test classifications compared with participants’ infection status. Therefore, the research question is clear as an intended diagnostic question, but its performance cannot be assessed from the posted outcome information.
3. Trial Design
This completed study, NCT01638312, is titled “Development of Method of Fructose Identification in Urine to Detect the Viral Infection.” The listed condition is Human Immunodeficiency Virus. The sponsor is Kaohsiung Medical University Chung-Ho Memorial Hospital. The record lists a start date of 2011-06 and a primary completion date of 2013-05. Enrollment is recorded as 50.
The study has two described groups: HIV-infected patients and healthy controls. The brief summary specifies 20 samples from HIV-infected patients and 30 from healthy controls. These are group descriptions, not evidence of random allocation. The record explicitly says the study does not have an intervention, and allocation is not stated. The groups therefore should not be treated as randomized arms or as necessarily comparable on characteristics other than the stated group labels.
Urine was collected once, with 10ml examined for fructose and fructose-diphosphate using the polarographic method. The primary outcome is described as the number of participants with a positive or negative waveform. The record gives a classification rule based on σ, but does not provide counts classified positive or negative, or any other outcome estimates.
The registry record lists one outcome measure and zero analyses. It does not report a statistical analysis plan, sample-size justification, interim analyses, participant flow, or detailed procedures for establishing HIV status. Although the study status is completed, completion alone does not establish that the proposed test was validated or that its diagnostic performance was estimated. The design is best understood as an early method-development investigation with a group comparison, rather than a randomized treatment trial.
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
| Stage | "HIV Infected Patients" | "Healthy Controls" |
|---|---|---|
| STARTED | 20 | 30 |
| COMPLETED | 20 | 30 |
| NOT COMPLETED | 0 | 0 |
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.
| Characteristic | Unit | "HIV Infected Patients" | "Healthy Controls" | Total |
|---|---|---|---|---|
| Participants analysed | 20 | 30 | 50 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 20 | 30 | 50 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Age, Continuous | years | 33.15 (SD 10.27) | 31.87 (SD 9.46) | 32.38 (SD 9.71) |
| Sex: Female, Male: Female | Participants | 1 | 18 | 19 |
| Sex: Female, Male: Male | Participants | 19 | 12 | 31 |
| Region of Enrollment: Taiwan | participants | 20 | 30 | 50 |
6. Primary Endpoint
The registry lists the primary outcome as Fructose Identification in Urine to Detect the Viral Infection : Number of Participants With Positive and Negative Waveform, measured over Participants provided urine samples once.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is described as the number of participants with a positive or negative waveform after urine testing. The registry’s interpretation rule classifies σ >= 10 units as abnormal positive and σ < 10 units as normal negative. The description also says that 50 is a reference to the center position on the X-axis and that the gap between X-axis values is σ. It does not explain the measurement scale or how the waveform is converted into a participant-level result in further detail.
A binary endpoint reduces a measurement to two categories. In a diagnostic-method study, this can make it possible to compare test classifications with a separately established infection status and estimate how often each classification is correct. That requires both test results and a reference classification, along with a clear account of how uncertain or unusable measurements are handled. The registry record does not report those comparisons or provide positive and negative counts.
The endpoint is relevant to the stated aim because the proposed method is intended to identify infection from a urine signal. However, the posted information does not establish that the threshold was selected independently of the data, nor does it describe a validation procedure. Without outcome counts and a reference-standard comparison, sensitivity, specificity, predictive values, and uncertainty around diagnostic performance cannot be assessed. The endpoint definition communicates the intended decision rule, but not whether the rule discriminated between the study groups.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record gives the study’s aim, group descriptions, specimen procedure, and a binary waveform classification rule. It does not report the number of participants classified as positive or negative, group-specific test results, or a statistical comparison. As a result, there is no posted estimate of how often the test identified samples from people with HIV infection, how often it returned a positive result among healthy controls, or how much uncertainty surrounds either quantity.
The status is listed as completed, and enrollment is recorded as 50. Those details describe the registry record’s study status and enrollment entry; they do not substitute for outcome data. The brief summary describes 20 HIV-infected patient samples and 30 healthy-control samples, but it does not state how many participants in either group had each waveform classification. The registry also lists zero analyses. No effect estimate, confidence interval, or p-value is reported in the record.
For a diagnostic test, the central interpretation depends on comparing the test result with an appropriate determination of infection status. A positive waveform among a participant already known to have HIV infection is not, by itself, enough to establish diagnostic accuracy; the corresponding group denominators and negative classifications also matter. Likewise, a negative result among healthy controls cannot be interpreted as evidence of specificity without the actual counts and a clearly described reference standard. These data are not reported in the registry record.
The threshold definition is stated: σ >= 10 units is abnormal positive, and σ < 10 units is normal negative. This defines how the record says the waveform should be categorized, but the record does not report whether the threshold was prespecified, how it was derived, or whether it was evaluated on data separate from those used to develop the method. Those omissions limit interpretation of a proposed diagnostic rule, even if outcome counts were available.
The absence of a reported analysis means that no conclusion about statistical evidence for separation between groups can be drawn from the posted information. No claim about the presence, size, precision, or clinical usefulness of a diagnostic effect is supported by the registry record. The appropriate reading is therefore descriptive: the study aimed to develop a urine-based electrochemical method and specified a positive/negative waveform rule, but its reported registry results do not show how the method performed.
9. Statistical Methods Explained
What does a binary endpoint represent?
A binary endpoint places each participant into one of two categories, such as positive or negative. In this study, the record defines the categories using a σ threshold: σ >= 10 units is positive, and σ < 10 units is negative. A binary result is easy to communicate, but it discards information about how far a measurement lies from the threshold. A measurement just on either side of a cutoff may be more alike than the two labels suggest. The registry record does not provide the underlying waveform measurements, so their distribution and proximity to the cutoff cannot be examined.
For diagnostic evaluation, a binary test result is usually compared with a reference classification of the condition. Counts from that comparison can be arranged as correct positive results, missed cases, false positive results, and correct negative results. Those counts allow estimation of sensitivity and specificity. The posted record does not report the required cross-classification, so these quantities cannot be derived.
Why does the comparison design matter?
The registry describes a group with HIV infection and a healthy-control group, with no intervention and no stated allocation process. This is not a randomized comparison. In a diagnostic-method study, random assignment is not necessarily the relevant design feature; the key issue is whether disease status and test results are established and assessed in a way that permits a fair diagnostic comparison. Differences between groups, selection procedures, and knowledge of status during measurement can affect how well an apparent test distinction generalizes. The record does not report details on these procedures or participant characteristics.
Comparing a group already identified as having the condition with healthy controls can also differ from evaluating a test in the population where it would actually be used. In general, clear separation between selected groups does not alone establish how a test performs in a broader or less selected population. This is a general methodological consideration, not a finding about this study.
What does a confidence interval convey?
In general, a confidence interval describes the uncertainty around an estimated quantity under the assumptions of the statistical method. Narrower intervals indicate greater precision, while wider intervals indicate less precision. For binary diagnostic outcomes, intervals around sensitivity or specificity would help show how much the observed performance could vary because of sampling uncertainty. The registry record reports no such estimates or intervals. Without outcome counts, there is no basis for calculating them.
A p-value, when used, addresses compatibility between observed data and a specified null model; it does not quantify the size or practical importance of a diagnostic effect. It also cannot replace an estimate with an interval. The registry record lists no analyses and reports no p-value. The statistical plan and any prespecified hypothesis are not reported in the registry record.
Why does the threshold need context?
A cutoff turns a continuous or graded signal into a decision category. The stated σ threshold gives a rule for labeling results, but interpreting that rule requires knowing how it was chosen and whether it was fixed before examining the study data. If a cutoff is selected to separate the same observations used to evaluate it, the apparent performance may be optimistic. Independent validation is one general way to assess whether performance persists in new observations. The registry record does not report threshold derivation or validation procedures, so neither can be assumed.
General diagnostic evaluation also considers the consequences of false positive and false negative classifications. A cutoff may trade one type of error against the other. The record does not report these error counts, a decision framework, or intended-use context in enough detail to assess that trade-off.
What can planning calculations show?
Sample-size planning uses assumptions about the effect to be detected, significance level, allocation, and statistical model to illustrate the amount of information a future study might need. Such calculations are planning illustrations, not observed power and not evidence that a study had a particular probability of finding a result. The stated planning assumptions for illustrations include a two-sided significance level of 0.05, equal allocation between groups, and a normal approximation, with the effect expressed as a fraction of an observed effect. These assumptions describe planning calculations, not the study’s own design. The registry record does not report the trial’s sample-size justification, and no observed effect is reported from which to interpret an effect-based planning illustration.
General methods should match the outcome and design. For binary data, analyses may compare proportions or estimate diagnostic measures with uncertainty intervals. When observations are not independent, a model may need to account for clustering or other structure; over-dispersion is a general concern when variability exceeds what a simple model assumes. The record does not report repeated measurements, clustering, or a fitted model, so no such structure can be attributed to this study.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists one primary outcome measure and zero analyses. It does not report multiple primary endpoints, multiple subgroup comparisons, or a multiplicity-adjustment procedure. With no reported analysis results, it is not possible to determine whether any additional comparisons were performed or how they were handled. The analysis plan is not reported in the registry record.
Missing-data handling is also not reported in the registry record. The record does not state how many participants completed urine collection, whether any specimens were unusable, whether any waveform could not be classified, or how incomplete measurements would be treated. These details matter because exclusions or unclassifiable results can affect the apparent distribution of positive and negative tests. Enrollment and the group sample descriptions do not establish the completeness of the endpoint data.
The analysis population is not described. The record does not say whether analyses were intended to include everyone enrolled, only those with usable urine measurements, or another defined set of participants. It also does not provide participant flow or explain whether any participants were excluded from analysis. The sponsor’s analysis, if any, is not reported in the registry record.
These reporting gaps are especially important for a diagnostic outcome, where an unclassifiable result may carry information rather than simply being an administrative omission. Without the number and handling of such results, the denominator behind any diagnostic measure would be unclear. Because no outcome counts or analysis are posted, neither the effect of missing data nor the impact of multiplicity can be assessed.
11. What the Result Does, and Does Not, Mean
The posted information establishes that this completed study sought to develop a polarographic urine method involving fructose and fructose-diphosphate, and that it defined a positive waveform using σ >= 10 units. It also describes a comparison involving HIV-infected patients and healthy controls, with urine collected once. These are statements about the study’s stated purpose and design.
The record does not report the number of positive or negative waveform results, diagnostic accuracy estimates, uncertainty intervals, or a statistical analysis. It therefore does not show whether the method distinguished the groups, how frequently it produced incorrect classifications, or how precise any estimated performance might be. Completion and enrollment are not evidence of a successful diagnostic result.
Even if group-level counts were available, interpreting a diagnostic method would require attention to how infection status was determined, how participants were selected, whether waveform readings were assessed without knowledge of group status, and whether the threshold was set before evaluation. The registry record does not report these details. It also does not document an independent validation sample or a comparison with a specified reference standard.
Accordingly, the record supports describing an intended method-development study and a proposed classification threshold. It does not support saying that the method can or cannot detect HIV, that it is accurate, or that it is suitable for any clinical use. Those conclusions would require outcome data and design information that are not reported in the registry record.
12. Why This Trial Matters Statistically
This study is statistically interesting because it connects a laboratory signal to a proposed binary diagnostic decision. The registry specifies a threshold for classifying urine waveform measurements, which makes the central analytical challenge visible: a measured signal must be translated into categories that correspond meaningfully to infection status. Evaluating that translation requires more than naming a cutoff. It requires transparent outcome counts, a reference classification, and estimates of error and uncertainty.
The record also illustrates why a completed status and an enrollment entry should be distinguished from reported evidence. A study can be marked completed while its registry entry lacks the result details needed to assess the stated research question. For readers, separating design information from outcome information prevents an intended method from being mistaken for a demonstrated diagnostic capability.
The group setup raises a general design consideration. A comparison between people identified as having HIV infection and healthy controls can be informative during early method development, but it does not automatically establish performance in the population where a test might be used. Selection, group differences, and the process used to establish status all shape interpretation. The registry record does not provide enough detail to assess those factors.
Finally, the record is a reminder that a threshold-based test can conceal useful information when measurements are reduced to positive and negative labels. Reporting the underlying signal, threshold rationale, classification counts, and uncertainty would help readers judge both the method and its limitations. Those elements are not reported in the registry record, so the statistical importance lies chiefly in identifying what evidence would be needed for evaluation, not in asserting an unreported result.
13. 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.
The main limitation for interpreting this study is that the registry record does not report outcome counts or an analysis. Although the primary endpoint is described as the number of participants with positive and negative waveforms, the numbers in each category are not reported. No estimates of diagnostic performance or their precision can therefore be assessed.
The outcome description leaves important measurement details unclear. It defines σ >= 10 units as positive and σ < 10 units as negative, and refers to a center position of 50 on the X-axis, but does not provide further information about the scale, signal processing, repeatability, or measurement quality. The record does not state how the threshold was developed or whether it was evaluated independently.
The comparator is described as healthy controls, while the other group is described as HIV-infected patients. Allocation is not stated, and the comparison is not randomized. The record does not report eligibility criteria, participant characteristics, how HIV status was established, or whether test assessment was blinded to group status. These omissions limit assessment of selection and measurement bias.
The registry record also does not report missing-data handling, participant flow, the analysis population, a statistical analysis plan, or a sample-size justification. It lists zero analyses. The adverse-event entries show zero counts for the listed categories, while deaths are recorded as null; these entries do not resolve the absence of diagnostic outcome information. In combination, the reporting gaps prevent a reliable assessment of test performance or its generalizability.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Development of Method of Fructose Identification in Urine to Detect the Viral Infection — NCT01638312.
- Registry record last updated 2015-10-05; status last verified 2012-09.
- Results first posted 2015-10-05.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
17. Record Summary
NCT01638312 is a completed method-development study sponsored by Kaohsiung Medical University Chung-Ho Memorial Hospital. Its listed condition is Human Immunodeficiency Virus. The study aimed to examine whether polarographic measurement of fructose and fructose-diphosphate in urine could help detect viral infection at an early stage.
The registry reports enrollment of 50 and describes 20 samples from HIV-infected patients and 30 from healthy controls. There was no intervention; participants provided urine once, with 10ml collected for examination. The primary endpoint is the number of participants with positive or negative waveforms, classified using the stated σ threshold.
The record lists one outcome measure and zero analyses. Positive and negative outcome counts, diagnostic estimates, and uncertainty measures are not reported in the registry record. The listed completion status and design description therefore do not establish how the proposed method performed.