This study developed and validated a 22-item medication information literacy scale (MILS) to assess the MIL of pregnant women, using a 5-point Likert scale with scores ranging from 22 to 110. The items covered five domains: medication information needs, medication information sources, medication information quality discrimination, medication information source awareness and medication-taking behavior. The MILS is designed to explore and quantify the ability of pregnant women to find, understand, evaluate and use medication information. The threshold was set at 80% of the total score [47]. The higher the score, the higher the level of MIL of pregnant women. The psychometric properties of the MILS were established in a Chinese context and showed good reliability and validity, which may accurately reflect the level of MIL in pregnant women. The MILS was developed comprehensively under the guidance of the conceptual framework (MIL) and a theoretical framework (Ellis’ Information-Seeking Behavior Model and the Comprehensive Model of Information Seeking). In the formal survey, the completion rate of the questionnaire was 93%, indicating high acceptability of the MILS in pregnant women.
The MILS was pilot tested involving 731 participants. Construct validity of the 22 item was good in the five domains which explained an accumulated 64.642% of the variance. The results of the principal component analysis revealed that all items had a factor loading greater than 0.6, further providing evidence of the factors solution [48]. The reliability coefficient of 0.871 was also good, denoting that the scale as a whole had internal consistency. The reliability of the MILS signifies dependability and consistency [49]. The validity and reliability of the MILS are vital as they enable health-care professions to feel confident that the respondent is competent with knowledge of medication use in pregnancy. According to the sensitivity analysis, there is no difference between the average score of MILS in the different level of education and in different stage of pregnancy and the overall average score. Therefore, MILS is suitable for pregnant women of any education level and any gestational age.
The medication information literacy (MIL) integrates information literacy(IL) and medication literacy(ML) [27]. The IL was defined as the ability of individuals to identify the type and scope of information required, efficiently access to needed information, critically evaluate the information and its sources, combine designated information into a personal knowledge base, and effectively apply information [50]. Pouliot et al. defined ML as the degree to which individuals can obtain, comprehend, communicate, calculate and process patient-specific information about their medications to make informed medication and health decisions [51]. The MIL emphasizes the comprehensive, critical, proactive and interactive capabilities of people in the process of acquiring medication information [52]. Pregnant women with adequate (or “high”) MIL are characterized with the ability to actively identify the need for medication information; efficiently obtain needed medication information; exactly comprehend required medication information; strictly evaluate medication information; and fully use medication information to make informed medication-related decisions [50, 51]. Moreover, in addition to general health outcomes, a few studies have found an association between inadequate HL and medication-related skills, including dosing errors [53], misunderstanding of prescription labels [54], poorer ability to take medication appropriately [55, 56], and lack of knowledge of dosing [57]. A lack of adequate MIL could result in poor medication adherence and the misunderstanding of medication-related information in pregnant women, which could in turn make pregnant women more prone to medication errors that adversely affect maternal and child health [58].
Pregnant women always have a higher risk perception of medication, which may negatively influence decisions in self-management, disease prevention, and health promotion, especially discourage them from taking medication as prescribed [59]. The behavior of medication usage is often related to the risk perception of medications [60]. Excessive risk perception may result in self-withdrawal of medication, and low risk perception may lead to self-medication. It is an indisputable fact that the compliance of medication during pregnancy is very low [10, 61]. What’s more, an observational cohort study by Toussaint et al. showed that self-medication was common before or during pregnancy, which might expose pregnant women to medication that may have negative effects on the fetus [1]. A study showed that respondents with a lower level of HL had more concerns about overuse and harmful effects of medication [62]. Therefore, extra attention should be given to pregnant women with inadequate MIL by healthcare professionals.
This cross-sectional survey showed that only 27.9% of pregnant women have adequate MIL, which was consistent with the results of Zhang et al [27]. Pregnant women have a higher need for medication information and are more cautious with medication use, but their MIL is generally at a low level and they lack the ability to discriminate between sources and quality of medication information. Weekes’ research showed that when using medications during pregnancy, the knowledge, information and tools required for health decisions were often lacking, which could result in pregnant women obtaining inconsistent or inaccurate medication information and needing adequate MIL to determine if a drug treatment poses a risk [63]. It is necessary and urgent to empower pregnant women to seek, comprehend, appraise and apply medication information. Similar to Vamos’study [17], the domain of medication information quality discrimination had the lowest score. Vamos et al. showed that pregnant women often feel anxious and fearful about online information, and they sought external assistance (from friends or healthcare providers) to assess the authenticity of the information [17]. These phenomena were in line with the low level of medication information quality discrimination in the current study.
The newly-developed MILS can serve as a screening tool to identify those pregnant women with inadequate MIL who may need additional assistance or intervention. A healthcare professional could help those women voice their concerns and offer relevant guidance to resolve these issues. Clinicians and nurses could use simpler terms, pictorial aids and/or visual medication schedules when educating or counselling these pregnant women to enhance their understanding of medication-related materials. In addition, the MILS could help healthcare professionals to recognize specific deficiencies areas where education about medications requires additional focus and improvement. The ultimate goal of medication education is to prevent potential errors or harm resulting from the misunderstanding of medication information in pregnant women.
Strengths and limitations
Previous studies have developed tools to measure medication-related HL, but they mainly related to specific medications or diseases such as an oral anticoagulation knowledge tool (OAK) and patient anticoagulation knowledge tool (PAK) [64, 65], Oral Anticoagulation Knowledge Tool (AKT) [66], the HIV Treatment Knowledge Scale (HIV-TKS) [67], with few studies involving pregnant women. Adequate MIL is important for pregnant women who require medication to help them accurately identify and take appropriate medication. The MILS is intended to be used in assessing the MIL of pregnant women to help healthcare professionals identify and educate pregnant women in an appropriate and timely manner.
Limitations in this study should be acknowledged. Pregnant women were recruited from hospitals in central China, which might not be representative of all pregnant women. Additional research in other countries or regions is needed for further verification, especially women living in lower socio-economic areas. A second limitation was the test-retest reliability finding showing that follow-up was relatively high, which may cause data bias. Lastly, the criterion-related validity of the MILS could not be conducted due to a lack of relevant scales. Scales in different languages are also expected in the future.