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 Evaluation of Efficacy of Photodynamic Therapy in Basal Cell Carcinoma (NCT00985829), a non-randomized phase 1 study. The primary outcome is Clinical Response to Photodynamic Therapy.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00985829 |
| Phase | Phase 1 |
| Condition | Basal Cell Carcinoma |
| Allocation | Non-Randomized |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 28 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Shahid Beheshti University of Medical Sciences |
| Results posted | Yes |
2. Clinical Question
Population
Patients with histologically proven basal cell carcinoma who were candidates for treatment with ALA-PDT. The registry record reports 28 enrolled participants, but does not state the number of lesions assessed for the primary outcome.
Intervention
Photodynamic therapy, described in the arm record as aminolevulinic acid photodynamic therapy (ALA-PDT).
Comparator
No comparator group is reported. The study is listed as a non-randomized, single-group study, so it does not provide a like-for-like control comparison.
Primary question
What clinical response categories were observed after the treatment course, and what factors were associated with response? The registry defines complete, partial, and no response, but the category counts and any analysis of associated factors are not reported in the registry record.
The stated purpose was to evaluate the efficacy of photodynamic therapy in basal cell carcinoma and factors that affect response rate. Statistically, the record supports describing the question as a within-group assessment of clinical response after treatment, rather than an estimate of the difference between two treatments. Without a comparator, the study cannot directly distinguish a treatment-associated response from changes or influences that might also occur without the intervention.
The primary outcome is expressed in lesions, while enrollment is reported as 28 participants. The registry record does not report how many lesions contributed to the outcome or how lesions were linked to participants. That distinction matters when interpreting response counts: lesions from the same participant may not represent independent observations. The record does not give an analysis addressing that issue.
3. Trial Design
This is a phase 1, completed, non-randomized, single-group study with no masking reported. The intervention is photodynamic therapy; the treatment arm is described as ALA-PDT for patients with histologically proven basal cell carcinoma who were candidates for that treatment. Enrollment is reported as 28. The sponsor is Shahid Beheshti University of Medical Sciences.
The registry dates the study start to 2008-01 and primary completion to 2008-07. The primary outcome timeframe is described as immediately after termination of the treatment course, with an average of 5 month after initiation of PDT. The registry does not provide further detail about treatment scheduling or the timing for individual participants.
Because the study has a single group and is non-randomized, it does not include a randomized treatment contrast. No separate control arm is listed, and the record explicitly cautions that the arms are not a like-for-like control comparison. Consequently, any clinical response description would be an account of outcomes among treated participants or lesions, not a controlled estimate of how outcomes differ under another treatment or no treatment.
The registry lists 6 outcome measures, including histologic resolution of lesion as a secondary outcome. It does not report outcome analysis entries. In particular, the record does not report the number of lesions assessed, the observed primary response counts, a statistical analysis plan, or results for histologic resolution. It also does not report how participants or lesions were selected for analysis. These omissions limit both the description of the observed outcomes and assessment of how representative they may be.
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.
Before assignment: Exclusion Criteria: rodent ulcer morphea type positive anti nuclear antibody test history of photosensitivity or photodermatosis or ingestion of phototoxic drugs during last month pregnancy breast feeding age\< 18 history of another therapeutic intervention for bcc during last 6 months
Overall Study
| Stage | Aminolevulinic Acid-Photodynamic Therapy (ALA-PDT) |
|---|---|
| STARTED | 28 |
| COMPLETED | 28 |
| NOT COMPLETED | 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 | Aminolevulinic Acid-Photodynamic Therapy (ALA-PDT) |
|---|---|---|
| Participants analysed | 28 | |
| Age Continuous | years | 59.1 (SD 12.7) |
| Sex: Female, Male: Female | Participants | 14 |
| Sex: Female, Male: Male | Participants | 14 |
6. Primary Endpoint
The registry lists the primary outcome as Clinical Response to Photodynamic Therapy, measured over immediately after termination of treatment course (with an average of 5 month after initiation of PDT).
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | lesions |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is titled Clinical Response to Photodynamic Therapy and is measured as a number of lesions. The registry defines three categories. Complete response means there was no visible or palpable lesion. Partial response means a visible or palpable lesion remained but its diameter had reduced. No response means a visible or palpable lesion remained and its diameter had not reduced.
This endpoint is intended to describe clinical change at the end of the treatment course, using visible or palpable findings and lesion diameter. Those categories separate disappearance of detectable lesion from reduction without disappearance and from no reduction. The stated assessment time is immediately after termination of the treatment course, with an average of 5 month after initiation of PDT.
For interpretation, the endpoint definition is not the same as an observed result. The registry record does not report how many lesions fell into each category, so the distribution of responses cannot be described from the posted results. Nor does the record report a numerical diameter-change measure or the method used to assess lesion size. The population field for the primary outcome is blank, and the outcome unit is lesions while enrollment is reported as participants. The number of lesions assessed and their relationship to participants are not reported in the registry record.
Histologic resolution of lesion is listed as a secondary outcome, but no definition or result for that outcome is reported. Clinical response and histologic resolution should therefore not be treated as interchangeable measures in interpreting the record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record gives a defined clinical outcome but does not post the outcome counts. It therefore does not establish how many lesions had complete response, partial response, or no response. No response estimate, uncertainty interval, or comparison can be reconstructed from the information reported. The stated purpose includes examining factors that affect response rate, but the record does not report which factors were assessed or any results for them.
The study design is important to what can be concluded. This is a non-randomized, single-group study without masking and without a listed comparator. A description of outcomes in this group would not, by itself, show what would have happened to comparable patients or lesions in the absence of photodynamic therapy or under an alternative intervention. The registry record itself notes that the arms are not a like-for-like control comparison. Here, only one group is described.
The endpoint is recorded in lesions, whereas enrollment is 28 participants. The registry record does not state the lesion count contributing to the endpoint or whether multiple lesions could contribute for an individual participant. If multiple lesions from a participant were included, outcomes within that participant might be related. General statistical principle: observations that are related do not carry the same information as an equal number of independent observations, so an analysis should account for the structure of the data. No such analysis is reported.
The timeframe indicates assessment immediately after the treatment course and gives an average of 5 month after initiation of PDT. This identifies the intended assessment point but does not describe how long each treatment course lasted or whether assessments occurred at a consistent interval for every participant. The record does not report longer-term follow-up for the primary endpoint.
Because no analysis entries or outcome counts are reported, it is not possible to assess precision, compare response categories, or judge the strength of evidence for any association. This is not evidence that the response rate was a particular value, nor does the absence of posted analysis establish that no analysis was performed. It means the registry record does not report those results. The appropriate reading is therefore limited to the study question, design, and endpoint definitions, with effectiveness conclusions left unresolved by the posted information.
9. Statistical Methods Explained
The record identifies a phase 1, single-group, non-randomized design with no masking. It does not report a statistical analysis plan, methods used to compare outcomes, or analysis entries. The statistical description must therefore distinguish features explicitly recorded from general principles that help explain what would be needed to interpret results.
What does a single-group design estimate?
A single-group study can describe outcomes observed among participants or lesions receiving the intervention. If response category counts were reported, those counts could describe the observed distribution in the analyzed group. A causal comparison requires a suitable contrast: for example, outcomes under the intervention compared with outcomes in a relevant comparison group. No such comparator is reported for this study. General principle: without a comparison group, observed outcomes cannot separate effects associated with treatment from other influences, such as the course of the condition, differences in participant characteristics, or the way outcomes are assessed. The record does not report methods to address those influences.
How should the categorical endpoint be understood?
The primary endpoint classifies lesions as complete response, partial response, or no response, according to visible or palpable findings and change in diameter. This is a categorical outcome, not a continuous measurement of diameter change. If category counts and a clear denominator were available, the categories could be described as counts or proportions. Those counts and denominators are not reported in the registry record, so no response frequency can be stated. The outcome population field is blank, and the record does not clarify the number of lesions evaluated.
General principle: a proportion is most informative when its numerator and denominator are clear and when the observations in the denominator are defined consistently. Here, enrollment is 28 participants, but the primary outcome unit is lesions. It is not reported whether the analysis included one lesion per participant or multiple lesions, or how any participant with more than one lesion was handled. That affects how any future reader should interpret a lesion-level summary and its uncertainty.
What do uncertainty measures add?
General explanation: a confidence interval describes a range of values compatible with the observed data under a stated statistical model and method. It communicates precision as well as the central estimate. A point estimate alone does not show how uncertain the estimate is. The registry record does not report response estimates or confidence intervals, and no interval can be derived without the missing counts and denominators.
For a comparison between groups, statistical methods can estimate a difference or another contrast and quantify its uncertainty. Since this study is listed as a single group, there is no reported between-group treatment contrast to interpret. A within-group outcome summary, if posted, would answer a descriptive question rather than provide the same evidence as a randomized comparison.
What does the sample-size illustration represent?
The record describes planning illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It states that the effect to detect is a stated fraction of the observed effect, and that non-time-to-event illustrations are expressed as participants per arm for specified power levels. These are planning assumptions, not details of the original trial design. The record does not report the trial's own sample-size justification or the numerical planning results in the registry record for this description. The observed effect needed to interpret those illustrations is also not reported.
General principle: planning calculations ask how many participants a future study might require under specified assumptions. They do not show the power achieved by a completed study, and a calculation based on an observed effect is particularly dependent on that effect estimate. Such illustrations should not be read as observed power or as evidence that the original enrollment was adequate. No sample-size justification for this study is reported in the registry record.
What can be said about statistical significance?
No p-value, confidence interval, model result, or other inferential analysis is reported. There is therefore no basis in the registry record to state whether a statistical test was performed or what it concluded. General principle: a p-value, when reported, addresses how compatible the data are with a specified null model under the test's assumptions; it does not by itself measure clinical importance or establish causation. In this record, the more basic elements needed for an outcome estimate—the response counts and denominator—are also absent.
The record lists 6 outcome measures and 0 analysis entries. The listed secondary outcome is histologic resolution of lesion. No analysis method for either the primary or secondary outcomes is reported, and the record does not say how missing or unevaluable lesions were handled. These gaps prevent assessment of model assumptions, precision, or whether the analyses matched the endpoint definitions.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 6 outcome measures, identifies clinical response as the primary outcome, and lists histologic resolution of lesion as a secondary outcome. However, the definitions and results for the other outcome measures are not reported in the registry record. It also contains no analysis entries. The record does not describe a plan for choosing among multiple outcomes, adjusting for multiple statistical tests, or distinguishing confirmatory from exploratory analyses.
General explanation: when several outcomes or statistical tests are examined, the chance of finding an apparently unusual result can increase if each is interpreted without regard to the others. A prespecified analysis plan can clarify which outcomes are primary and how additional analyses will be interpreted. Because no statistical plan or analysis results are reported, it is not possible to determine whether multiplicity was addressed or how it might affect interpretation.
Missing-data handling is also not reported. The registry record does not say whether all enrolled participants completed treatment, whether all lesions could be assessed, how unevaluable findings were classified, or whether any observations were excluded. No analysis population is defined, and the record does not report whether the outcome assessment included all 28 enrolled participants.
These omissions should not be read as proof that data were missing or that analyses were conducted improperly. They mean that the registry record does not report the information needed to assess missingness, analysis populations, or multiplicity. Without outcome denominators and analytic details, the completeness and precision of any response summary cannot be evaluated.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Aminolevulinic Acid-Photodynamic Therapy (ALA-PDT) | 0 | 28 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Aminolevulinic Acid-Photodynamic Therapy (ALA-PDT) | 2 of 28 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Aminolevulinic Acid-Photodynamic Therapy (ALA-PDT) |
|---|---|---|
| local intolerable pain | Skin and subcutaneous tissue disorders | 2 of 28 |
The registry safety summary lists 28 participants at risk for serious adverse events and 0 affected. It also lists 28 at risk for other adverse events and 2 affected. These figures are recorded for the ALA-PDT group. The registry record does not provide the serious adverse event terms, and no top serious adverse event terms are listed. Deaths are not reported in the registry record.
These figures are a registry summary, not a complete description of the nature, timing, severity, or clinical course of events. The record does not explain how events were collected, the period over which participants were monitored, or how the figures relate to treatment exposure. It also does not provide detail about the 2 other adverse events. The category labels should not be used to infer event type or causation.
General principle: a count of zero reported serious adverse events does not by itself establish the absence of risk, particularly when the record does not describe follow-up and event ascertainment. These figures should be read narrowly as the counts posted for this group, not as a comparison with another treatment or as a complete safety assessment.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a phase 1, single-group study evaluated photodynamic therapy in patients with basal cell carcinoma who were candidates for ALA-PDT. It defines a clinical endpoint based on visible or palpable lesion findings and change in diameter, and reports 28 enrolled participants. It also lists histologic resolution of lesion as a secondary outcome.
The record does not report the number of lesions with complete, partial, or no response. It does not report a response rate, analysis of factors associated with response, histologic-resolution results, or statistical uncertainty. As a result, the posted information does not allow a quantitative assessment of the clinical outcomes. This absence of results should not be interpreted as a favorable or unfavorable result.
The design also limits what an outcome description could establish. There is no reported comparator group, and the study is non-randomized with no masking. A response observed in a treated group would not by itself show how outcomes would differ under another intervention or without treatment. The registry record explicitly identifies the study as a non-randomized comparison in which the arms are not a like-for-like control comparison; the design details list a single group.
The primary outcome is measured in lesions, but the number of lesions assessed and their relationship to the 28 enrolled participants are not reported. This leaves the analysis denominator unclear. The timing is described as immediately after the treatment course, with an average of 5 month after initiation of PDT, and no longer-term primary outcome follow-up is reported.
Accordingly, the record supports a description of the study question, intervention, design, endpoint definitions, and limited safety counts. It does not support a conclusion about the magnitude or certainty of clinical response, a treatment comparison, or the association of particular factors with response.
13. Why This Trial Matters Statistically
This record illustrates a basic distinction between defining an outcome and reporting an outcome. The primary endpoint is described in detail, including the clinical criteria for complete, partial, and no response. Yet the corresponding category counts and denominator are not reported. Without them, readers cannot calculate or evaluate even a descriptive response summary.
It also highlights why the unit of analysis matters. Enrollment is reported as participants, while the primary outcome is measured in lesions. The registry record does not state how many lesions were assessed or whether multiple lesions could belong to one participant. General statistical principle: when multiple observations arise from the same person, their outcomes may be related. Clear reporting of the participant and lesion counts, together with an appropriate analysis description, helps readers understand the effective information in a result.
The design makes the intended inference important to state precisely. A single-group, non-randomized evaluation can describe outcomes in the group studied, but it does not provide a randomized comparison. Keeping descriptive findings separate from comparative claims is essential when the record contains no control group and no posted analysis.
Finally, the registry lists several outcome measures but no analysis entries. That makes transparent outcome reporting, denominators, missing-data handling, and analytic methods especially important for interpretation. The record is useful for identifying the research question and measurement definitions, while its missing results show why a complete registry account needs both prespecified outcomes and their observed findings.
14. 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 principal limitation for interpreting results is that response counts are not reported. The registry defines three primary response categories but gives no number of lesions in each category, no denominator for the endpoint, and no uncertainty estimates. The primary outcome population field is blank. As enrollment is reported as participants and the endpoint unit is lesions, the relationship between participants and analyzed lesions remains unclear.
The design is non-randomized and single-group, with no masking and no listed comparator. This means the record does not provide a controlled treatment contrast. The factors that the study intended to examine are not named, and no results relating factors to response are reported. The registry does not provide a statistical analysis plan or analysis entries.
The timeframe is stated as immediately after the treatment course, with an average of 5 month after initiation of PDT. The record does not report individual assessment timing, longer-term follow-up for the primary endpoint, or methods for assessing lesion diameter. Histologic resolution is listed as a secondary outcome, but its definition and result are not reported.
Other information needed for a full assessment is also absent: the sample-size justification, analysis populations, missing-data procedures, and any approach to multiple outcomes or tests are not reported in the registry record. These are limits of the information recorded; they do not establish that the corresponding procedures were absent from the study itself.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Evaluation of Efficacy of Photodynamic Therapy in Basal Cell Carcinoma — NCT00985829.
- Registry record last updated 2009-12-22; status last verified 2009-11.
- Results first posted 2009-12-22.
- 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.
18. Record Summary
The registry record describes NCT00985829, Evaluation of Efficacy of Photodynamic Therapy in Basal Cell Carcinoma. It is listed as a completed phase 1, non-randomized, single-group study with no masking, sponsored by Shahid Beheshti University of Medical Sciences. Enrollment is reported as 28, and the intervention is photodynamic therapy, described in the arm record as ALA-PDT for patients with histologically proven basal cell carcinoma who were candidates for that treatment.
The primary outcome is clinical response measured in lesions and categorized as complete, partial, or no response. Its timeframe is immediately after termination of the treatment course, with an average of 5 month after initiation of PDT. Histologic resolution of lesion is listed as a secondary outcome. The record reports 6 outcome measures and 0 analysis entries, but does not report primary response counts or secondary outcome results. It lists 0 serious adverse events among 28 at risk and 2 other adverse events among 28 at risk; deaths are not reported in the registry record.