Data Characteristics
Stability study data primarily originates from various experimental reports, analysis certificates, batch production records, and quality standard documents. These documents are typically in PDF, Word, or scanned image formats, with varying degrees of content structure. Data update frequency is relatively low, mainly concentrated during the R&D phase or product lifecycle changes. Documents contain extensive tabular data, such as active ingredient content, impurity levels, and pH values at different time points and under various storage conditions. They also include textual descriptions, such as experimental methods, observed phenomena, and deviation handling. Field names often contain specialized abbreviations and units, for example, ICH Q1A(R2), RH%, °C, ug/mL, NLT (not less than), NMT (not more than).
Constraints Imposed by These Characteristics on Knowledge Base Retrieval and Recall
The high density of tabular data in stability study documents requires the knowledge base to effectively parse and index structured information. Simple text segmentation can lead to the loss of critical data associations. The use of specialized terminology and abbreviations challenges the vocabulary coverage and semantic association capabilities of text understanding models. Low document update frequency means that initially built knowledge base content has a longer lifecycle, but new data (e.g., new batches, new formulations) requires timely incremental updates. The specificity of fields and units demands accurate matching or understanding of their inherent meaning during retrieval, preventing recall failures due to inconsistent units or differing abbreviations. Furthermore, the need for time-series data queries, such as "degradation products of a certain drug after 12 months under 40°C/75%RH conditions," requires the retrieval system to understand multi-condition combined queries.
Configuration Guidelines
| Configuration Item | Recommended Value | Rationale |
|---|---|---|
Chunk size (Chunk Size) | 500–800 characters | Balances the completeness of tabular and textual information, preventing excessive length from introducing irrelevant interference and excessive brevity from fragmenting critical data. |
Overlap Length | 100–150 characters | Ensures contextual continuity at chunk boundaries, particularly useful for semantic understanding across tables or paragraphs. |
Recall count (Number of Retrieved Chunks) | Top 5–8 chunks | Stability study queries often require multiple relevant data points for comprehensive judgment. Increasing the number of retrieved chunks covers more potentially relevant information. |
Similarity threshold (Similarity Threshold) | Calibrate based on actual measurements | Adjust through a test set to ensure high relevance recall for the specialized vocabulary and data patterns in stability studies. |
Rerank result count (Number of Reranked Chunks) | Top 3–5 chunks | Performs a secondary sorting on the retrieved chunks, selecting the most relevant segments to improve the precision of the final presentation. |
maxContext | 4096 tokens | Ensures the model can receive a sufficiently long context to handle complex queries involving multiple time points and metrics. |
Three Common Mistakes
- Query results lack critical tabular data or numerical values because the table structure was not correctly identified and indexed during document parsing, leading to the loss of structured information.
- System logs show
EMBEDDING_MODEL_ERRORorRE-RANK_MODEL_ERROR. This typically indicates that the configured text understanding model or reranking model cannot process the specialized terminology and abbreviations unique to stability studies. - Answers are vague and fail to focus on specific data within the knowledge base. This might be due to a
Similarity threshold(Similarity Threshold) set too high, filtering out relevant but not perfectly matching segments, orRecall count(Number of Retrieved Chunks) being too low, failing to provide sufficient contextual information.
How to Verify Configuration
- Select representative stability study questions and execute queries. Check if the returned results include the key metrics, time points, and experimental conditions mentioned in the question.
- Compare query results with the original documents. Verify that the recalled text segments correspond accurately, especially data in tables and descriptive text.
- Adjust
Similarity threshold(Similarity Threshold) andRecall count(Number of Retrieved Chunks). Observe changes in the relevance and completeness of the recalled content until a satisfactory balance is achieved on the test set. - Monitor system logs to ensure no model processing errors or timeouts occur during text understanding and reranking. Check if the
maxContextparameter meets actual query requirements.
The values provided are common starting points and should be measured against your own samples.
Question material comes from public community discussions. Configuration values are common starting points and should be measured against your own samples. Verified on 2026-09-21.